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Litecoin Price Chart (LTC) | Coinbase

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Litecoin is a cryptocurrency that uses a faster payment confirmation schedule and a different cryptographic algorithm than Bitcoin.

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Litecoin Rating Report

2018-08-16

Litecoin creator Charlie Lee created Litecoin via mimicking Bitcoin’s core code, and managed to survive in the sea of clone coins, gradually developing strongly. In terms of the technical layer, Litecoin made improvements concentrated in the consensus mechanism layer, and through a new hashing mechanism, lowered the barrier to entry for miners, and raised the difficult of concentrating hashing power, as well as providing a certain degree of resistance to ASIC mining. However, power still became concentrated and decentralisation wasn’t achieved. This was an inevitable result of the increase in popularity of the token, and a result of the relationship between cost and benefit for miners. As a token very similar to bitcoin, to a certain extent, Litecoin can work a test ground for Bitcoin, and in a situation where it can lower the cost of experimentation, Bitcoin may need to attain a plan for improvement. When compared with other coins that have failed, there are many reasons why it has been able to gain attention. Aside from analysis of the text, “Litecoin is silver to Bitcoin’s gold”, it as a supplement to Bitcoin, and is use in areas that Bitcoin can’t touch is one of its major aspects through which it can be promoted. As a payment token, Litecoin faces the same problem other tokens do: high volatility. Currently, the degree of support by merchants on the market of Litecoin is not enough to be able to make it widely accepted as a medium of payment. Litecoin in the top echelon of payment-type tokens. Additionally, in the regulatory realm, due to different regulations throughout the world, as well as a lack of a complete regulatory framework, the possibility of influence by external factors is relatively large. For thesereasons, TokenInsight gives Litecoin a rating of BBB. The outlook is stable.

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Litecoin (LTC) price: News & Live Chart – Trading Analysis …

What is Litecoin (LTC)?

Litecoin is a digital currency, abbreviated as LTC, distributed in a decentralized network and is one of the world’s largest cryptocurrencies. Litecoin launched in October, 2011 as a direct derivative of Bitcoin and its blockchain. Litecoin offered a key advantage over Bitcoin in the form of faster transactions and thus higher potential liquidity-ultimately resulting in lower transaction costs.

Litecoin was the first of the top 5 cryptocurrencies in market capitalization to implement the Segregated Witness transaction format. Also known as SegWit, the new protocol allowed for potential speed and security improvements on the original Litecoin software and enabled the use of the so-called Lightning Network. Here the purpose of the secondary network is to enable faster off-blockchain transactions which are ultimately aggregated and broadcast to the blockchain itself.

The development and performance of Litecoin has tracked Bitcoin, and therefore has quickly become the world’s second-largest cryptocurrency in terms of total market capitalization.

In the future we expect Litecoin to track the trajectory of other major cryptocurrencies quite closely. Where it stands to gain is as a more technologically-advanced version of Bitcoin. And indeed price of LTC has thus far outperformed BTC since Litecoin adopted SegWit in May, 2017.

You can track Litecoin prices on our currency chart, and read all the latest Litecoin news and analysis to support your cryptocurrency day trading.

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Litecoin (LTC) – Live trades, prices and market cap.

Litecoin (LTC) – Live trades, prices and market cap.

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What is litecoin?

Litecoin is a peer-to-peer cryptocurrency in many regards similar to Bitcoin. Coins are created and transfered using an open source cryptographic protocol and are not managed by any central authority. Thanks to the adoption of Segregated Witness, and the Lightning Network, Litecoin has some technical advantages over Bitcoin and other major cryptocurrencies. It is capable of handling a greater number of transactions in a given time and thus reducing potential bottlenecks, as seen with Bitcoin. Also, payment cost of Litecoin is nearly zero and its payment speed is approximately four times greater than that of Bitcoin.

Litecoin was released via an open-source client on GitHub on October 7, 2011 by Charlie Lee, a former Google employee. The Litecoin network went live on October 13, 2011. It was a fork of the Bitcoin Core client, differing primarily by having a decreased block generation time (2.5 minutes), increased maximum number of coins, different hashing algorithm (scrypt, instead of SHA-256), and a slightly modified GUI. During the month of November 2013, the aggregate value of Litecoin experienced massive growth which included a 100% leap within 24 hours. Litecoin reached a $1 billion market capitalization in November 2013

Like all cryptocurrencies, litecoin is not issued by a government, which historically has been the only entity that society trusts to issue money. Instead being regulated by a Federal Reserve and coming off a press at the Bureau of Engraving and Printing, litecoins are created by the elaborate procedure called mining, which consists of processing a list of litecoin transactions. Unlike traditional currencies, the supply of litecoins is fixed. There will ultimately be only 84 million litecoins in circulation and not one more. Every 2.5 minutes (as opposed to 10 minutes for bitcoin) , the litecoin network generates a what is called a blocka ledger entry of recent litecoin transactions throughout the world. And here is where litecoins inherent value derives.

Read more: What Is Litecoin And How Does It Work?

The incentive for mining is that the first miner to successfully verify a block is rewarded with 50 litecoins. The number of litecoins awarded for such a task reduces with time. In October of 2015 it will be halved, and the halving will continue at regular intervals until the 84,000,000th litecoin is mined. But could one unscrupulous miner change the block, enabling the same litecoins to be spent twice? No. The scam would be detected immediately by some other miner, anonymous to the first. The only way to truly game the system would be to get a majority of miners to agree to process the false transaction, which is practically impossible.

Read more: What Is Litecoin And How Does It Work?

Storing litecoin. If you want buy litecoin or you already have some litecoin you have to find find some save place where you will put your litecoin. You have lot of option it depend of your idea what you want done with your litecoin. Most used option is putting your litecoin it to software wallet you can genereate software wallet for free and you have lot of time on software wallet this option is relatively save but not much practicaly. Second most used variant is put your litecoin in to some cryptocurenci stock where your litecoin is not some secured as in Software wallet but you have more option what you can done with your litecoin you can sell your litecoin you can buy more litecoin you can exchange your litecoi you can lend your litecoin and make some profit of them it only depend of you. Newest way is put your litecoin in to hardware wallet be casrfull there is differencsi between hardware and fostware wallet in hardware wallet your litecoin is on absoultly save anyone can not steal your litecoin but if you lost your hardware wallet hardware wallet is technolgical simular to flash drive your will lose all your litecoin be carefull and this oponinin is not much practicaly. It only depend on you what type of variant is best for you.

Litecoin transaction fee cost fee cents bitcoin transaction fee is about dollars. Litecoin has faster network transaction is much fastert then in bitcoin network normal transaction takes 2 minnuste in bitcoin blockchain normal transaction take 10 minute. Total annound bitcoin is 21 million coin and litecoin has 84 million coin. Different algorim bitcoin use Bitcoins SHA-256 litecoin use Litecoins Scrypt . Bitcoin has a biggest market capitalistion in cryptocurrenci litecoin in now in six postion but in future litecoin should have one of the biggest market cappilastion.

Once a currency reaches a critical mass of users who are confident that the currency is indeed what it represents and probably wont lose its value, it can sustain itself as a method of payment. Litecoin isnt anywhere near universally accepted, as even its own founders admit that it has fewer than 100,000 users. (Even bitcoin probably has less than half a million total users.) But as cryptocurrencies become more readily accepted and their values stabilize, one or two of thempossibly including litecoinwill emerge as the coin(s) of the digital realm.

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Litecoin (LTC) Price, Chart, Info | CoinGecko

About Litecoin

Litecoin is a peer-to-peer cryptocurrency created by Charlie Lee. It was created based on the Bitcoin protocol but differs in terms of the hashing algorithm used. Litecoin uses the memory intensive Scrypt proof of work mining algorithm. Scrypt allows consumer-grade hardware such as GPU to mine those coins.

Why Litecoin?Litecoin is a cryptocurrency that has evolved from Bitcoin after its own popularity in the industry, this alternative, or altcoin has emerged to allow investors to diversify their digital currency package, according to Investopedia. Litecoin is one of the most prominent altcoins and was created by former Google employee and Director of Engineering at Coinbase, Charlie Lee. Litecoin was the first to alter Bitcoin and the most significant difference is that it takes 2.5 minutes for Litecoin to generate a block, or transaction, in comparison to Bitcoin’s 10 minutes.

While this matters little to traders, miners who use hardware to run Bitcoin’s network cannot switch over to Litecoin. This keeps bigger mining conglomerates away from Litecoin because they cannot easily optimize their profits by swapping to another coin, contributing to a more decentralized experience. Litecoin also has bigger blocks, and more coins in circulation, making it more affordable and swift when transacting, Investopedia explained.

As explained above, Litecoin can transact a lot faster than Bitcoin, but there are also a number of other characteristics that investors need to know before trading. Litecoin can handle higher volumes of transactions because of the capability of transacting faster and if Bitcoin attempted to transact on the scale of its altcoin, a code update would be needed. However, Litecoins blocks would be larger, but with more orphaned blocks’. The faster block time of litecoin reduces the risk of double spending attacks – this is theoretical in the case of both networks having the same hashing power.

Litecoin Technical Details:The transaction confirmation time taken for Litecoin is about 2.5 minutes on average (as compared to Bitcoin’s 10 minutes). The Litecoin network is scheduled to cap at 84 million currency units.

Litecoin has inspired many other popular alternative currencies (eg. Dogecoin) because of its Scrypt hashing algorithm in order to prevent ASIC miners from mining those coins. However it is said that by the end of this year, Scrypt ASIC will enter the mass market.

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Litecoin (LTC): Rejected at $40, this downtrend could last longer

The market is in the red on Tuesday. However, there was a marginal recovery in the market yesterday. Litecoin price, for example, bounced from the support at the 38.2% Fibonacci retracement level taken between the highs of $41.59 and the lows of $22.62. The bullish correction managed to pull above the 50% Fib level but fizzled out short-of $34.00.

Litecoin started this years trading with a strong upside momentum. The bulls maintained itsposition above the trendline support while trading higher highs and higher lows. In fact, there was a break above the resistance at $40. Unfortunately, they could not sustain the momentum as the trend culminated in a lower correction forming lows towards $30.00.

Meanwhile, Litecoin is trading at $31.8 and is below the 1-hour Simple Moving Averages (SMA). The price is dancing with the 50 SMA while the immediate upside is limited by the 100-day SMA. LTC buyers must push the crypto above $34.00 in order for them to embark on a recovery journey towards the psychological $40.00.

On the flipside, if the current bearish trend progresses, LTC/USD is expected to find refuge at $30.00 (38.2% Fib level). Below this level, the buyers will take solace at recent lows around $22.5.

Taking a broader look at the chart, a bullish trend could be brewing in the background since the Moving Average Convergence Divergence (MACD) is trending to the upside from the dip at -1.57. Likewise, the Relative Strength Index (RSI) on the same chart, defended its position above the oversold region. Besides, it has recovered to the current position at 50.00.

LTC/USD 1-hour chart

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Litecoin (LTC): Rejected at $40, this downtrend could last longer

Colonization of Mars – Wikipedia

Mars is the focus of much scientific study about possible human colonization. Mars’s surface conditions and past presence of water make it arguably the most hospitable planet in the Solar System besides Earth. Mars requires less energy per unit mass (delta-v) to reach from Earth than any planet, other than Venus.

Permanent human habitation on other planets, including Mars, is one of science fiction’s most prevalent themes. As technology advances, and concerns about humanity’s future on Earth increase, arguments favoring space colonization gain momentum.[2][3] Other reasons for colonizing space include economic interests, long-term scientific research best carried out by humans as opposed to robotic probes, and sheer curiosity.

Both private and public organizations have made commitments to researching the viability of long-term colonization efforts and to taking steps toward a permanent human presence on Mars. Space agencies engaged in research or mission planning include NASA, Roscosmos, and the China National Space Administration. Private organizations include SpaceX, Lockheed Martin, and Boeing.

All of the early human mission concepts to Mars as conceived by national governmental space programssuch as those being tentatively planned by NASA, Rocosmos and ESAwould not be direct precursors to colonization. They are intended solely as exploration missions, as the Apollo missions to the Moon were not planned to be sites of a permanent base.

Colonization requires the establishment of permanent habitats that have potential for self-expansion and self-sustenance. Two early proposals for building habitats on Mars are the Mars Direct and the Semi-Direct concepts, advocated by Robert Zubrin.[4]

As of 2018, SpaceX is funding and developing a series of Mars-bound cargo flights with the BFR rocket and spaceship system as early as 2022, followed by the first crewed flight to Mars on the next launch window in 2024.[5][6][7] During the first phase, the goal will be to launch several BFRs to transport and assemble a methane/oxygen propellant plant and to build up a base in preparation for an expanded surface presence.[8] A successful colonization would ultimately involve many more economic factorswhether individuals, companies, or governmentsto facilitate the growth of the human presence on Mars over many decades.[9][10][11]

Earth is similar to Venus in bulk composition, size and surface gravity, but Mars’s similarities to Earth are more compelling when considering colonization. These include:

Conditions on the surface of Mars are closer to the conditions on Earth in terms of temperature and sunlight than on any other planet or moon, except for the cloud tops of Venus.[38] However, the surface is not hospitable to humans or most known life forms due to the radiation, greatly reduced air pressure, and an atmosphere with only 0.1%oxygen.

In 2012, it was reported that some lichen and cyanobacteria survived and showed remarkable adaptation capacity for photosynthesis after 34days in simulated Martian conditions in the Mars Simulation Laboratory (MSL) maintained by the German Aerospace Center (DLR).[39][40][41] Some scientists think that cyanobacteria could play a role in the development of self-sustainable crewed outposts on Mars.[42] They propose that cyanobacteria could be used directly for various applications, including the production of food, fuel and oxygen, but also indirectly: products from their culture could support the growth of other organisms, opening the way to a wide range of life-support biological processes based on Martian resources.[42]

Humans have explored parts of Earth that match some conditions on Mars. Based on NASA rover data, temperatures on Mars (at low latitudes) are similar to those in Antarctica.[43] The atmospheric pressure at the highest altitudes reached by piloted balloon ascents (35km (114,000 feet) in 1961,[44] 38km in 2012) is similar to that on the surface of Mars. However, the pilots were not exposed to the extremely low pressure, as it would have killed them, but seated in a pressurized capsule.[45]

Human survival on Mars would require living in artificial Mars habitats with complex life-support systems. One key aspect of this would be water processing systems. Being made mainly of water, a human being would die in a matter of days without it. Even a 58% decrease in total body water causes fatigue and dizziness and a 10% decrease physical and mental impairment (See Dehydration). A person on Earth uses 70140litres of water per day on average.[46] Through experience and training, astronauts on the ISS have shown it is possible to use far less, and that around 70% of what is used can be recycled using the ISS water recovery systems. Similar systems would be needed on Mars, but would need to be much more efficient, since regular robotic deliveries of water to Mars would be prohibitively expensive (the ISS is supplied with water four times per year).[47] Potential access to in-situ water (frozen or otherwise) via drilling has been investigated by NASA.[48]

Mars presents a hostile environment for human habitation. Different technologies have been developed to assist long-term space exploration and may be adapted for habitation on Mars. The existing record for the longest consecutive space flight is 438days by cosmonaut Valeri Polyakov,[49] and the most accrued time in space is 878days by Gennady Padalka.[50] The longest time spent outside the protection of the Earth’s Van Allen radiation belt is about 12days for the Apollo 17 moon landing. This is minor in comparison to the 1100-day journey[51] planned by NASA as soon as the year 2028. Scientists have also hypothesized that many different biological functions can be negatively affected by the environment of Mars colonies. Due to higher levels of radiation, there are a multitude of physical side-effects that must be mitigated.[52] In addition Martian soil contains high levels of toxins which are hazardous to human health.

The difference in gravity would negatively affect human health by weakening bones and muscles. There is also risk of osteoporosis and cardiovascular problems. Current rotations on the International Space Station put astronauts in zero gravity for six months, a comparable length of time to a one-way trip to Mars. This gives researchers the ability to better understand the physical state that astronauts going to Mars would arrive in. Once on Mars, surface gravity is only 38% of that on Earth.[53] Upon return to Earth, recovery from bone loss and atrophy is a long process and the effects of microgravity may never fully reverse.

There are also severe radiation risks on Mars that can influence cognitive processes, deteriorate cardiovascular health, inhibit reproduction, and cause cancer.

Due to the communication delays, new protocols need to be developed in order to assess crew members’ psychological health. Researchers have developed a Martian simulation called HI-SEAS (Hawaii Space Exploration Analog and Simulation) that places scientists in a simulated Martian laboratory to study the psychological effects of isolation, repetitive tasks, and living in close-quarters with other scientists for up to a year at a time. Computer programs are being developed to assist crews with personal and interpersonal issues in absence of direct communication with professionals on earth.[54] Current suggestions for Mars exploration and colonization are to select individuals who have passed psychological screenings. Psychosocial sessions for the return home are also suggested in order to reorient people to society.

Various works of fiction put forward the idea of terraforming Mars to allow a wide variety of life forms, including humans, to survive unaided on Mars’s surface. Some ideas of possible technologies that may be able to contribute to the actual terraforming of Mars have been conjectured, but none would be able to bring the entire planet into the Earth-like habitat pictured in science fiction.[55]

Mars has no global magnetosphere as Earth does. Combined with a thin atmosphere, this permits a significant amount of ionizing radiation to reach the Martian surface. The Mars Odyssey spacecraft carries an instrument, the Mars Radiation Environment Experiment (MARIE), to measure the radiation. MARIE found that radiation levels in orbit above Mars are 2.5 times higher than at the International Space Station. The average daily dose was about 220Gy (22mrad) equivalent to 0.08Gy per year.[56] A three-year exposure to such levels would be close to the safety limits currently adopted by NASA.[citation needed]Levels at the Martian surface would be somewhat lower and might vary significantly at different locations depending on altitude and local magnetic fields. Building living quarters underground (possibly in Martian lava tubes which are already present) would significantly lower the colonists’ exposure to radiation. Occasional solar proton events (SPEs) produce much higher doses.

Much remains to be learned about space radiation. In 2003, NASA’s Lyndon B. Johnson Space Center opened a facility, the NASA Space Radiation Laboratory, at Brookhaven National Laboratory, that employs particle accelerators to simulate space radiation. The facility studies its effects on living organisms, as well as experimenting with shielding techniques.[60] Initially, there was some evidence that this kind of low level, chronic radiation is not quite as dangerous as once thought; and that radiation hormesis occurs.[61] However, results from a 2006 study indicated that protons from cosmic radiation may cause twice as much serious damage to DNA as previously estimated, exposing astronauts to greater risk of cancer and other diseases.[62] As a result of the higher radiation in the Martian environment, the summary report of the Review of U.S. Human Space Flight Plans Committee released in 2009 reported that “Mars is not an easy place to visit with existing technology and without a substantial investment of resources.”[62] NASA is exploring a variety of alternative techniques and technologies such as deflector shields of plasma to protect astronauts and spacecraft from radiation.[62]

In September 2017, NASA reported radiation levels on the surface of the planet Mars were temporarily doubled, and were associated with an aurora 25-times brighter than any observed earlier, due to a massive, and unexpected, solar storm in the middle of the month.[63]

Mars requires less energy per unit mass (delta V) to reach from Earth than any planet except Venus. Using a Hohmann transfer orbit, a trip to Mars requires approximately nine months in space.[64] Modified transfer trajectories that cut the travel time down to four to seven months in space are possible with incrementally higher amounts of energy and fuel compared to a Hohmann transfer orbit, and are in standard use for robotic Mars missions. Shortening the travel time below about six months requires higher delta-v and an exponentially[clarification needed][an exponential function of what?] increasing amount of fuel, and is difficult with chemical rockets. It could be feasible with advanced spacecraft propulsion technologies, some of which have already been tested to varying levels, such as Variable Specific Impulse Magnetoplasma Rocket,[65] and nuclear rockets. In the former case, a trip time of forty days could be attainable,[66] and in the latter, a trip time down to about two weeks.[4] In 2016, a University of California scientist said they could further reduce travel time for an robotic probe to Mars down to “as little as 72 hours” with the use of a “photonic propulsion” system instead of the fuel-based rocket propulsion system.[67]

During the journey the astronauts would be subject to radiation, which would require a means to protect them. Cosmic radiation and solar wind cause DNA damage, which increases the risk of cancer significantly. The effect of long-term travel in interplanetary space is unknown, but scientists estimate an added risk of between 1% and 19% (one estimate is 3.4%) for men to die of cancer because of the radiation during the journey to Mars and back to Earth. For women the probability is higher due to generally larger glandular tissues.[68]

Mars has a surface gravity 0.38 times that of Earth, and the density of its atmosphere is about 0.6% of that on Earth.[69] The relatively strong gravity and the presence of aerodynamic effects make it difficult to land heavy, crewed spacecraft with thrusters only, as was done with the Apollo Moon landings, yet the atmosphere is too thin for aerodynamic effects to be of much help in aerobraking and landing a large vehicle. Landing piloted missions on Mars would require braking and landing systems different from anything used to land crewed spacecraft on the Moon or robotic missions on Mars.[70]

If one assumes carbon nanotube construction material will be available with a strength of 130 GPa then a space elevator could be built to land people and material on Mars.[71]A space elevator on Phobos (a Mars moon) has also been proposed.[72]

Colonization of Mars would require a wide variety of equipmentboth equipment to directly provide services to humans and production equipment used to produce food, propellant, water, energy and breathable oxygenin order to support human colonization efforts. Required equipment will include:[4]

According to Elon Musk, “even at a million people [working on Mars] you’re assuming an incredible amount of productivity per person, because you would need to recreate the entire industrial base on Mars… You would need to mine and refine all of these different materials, in a much more difficult environment than Earth”.[75]

In order to function at all the colony would need the basic utilities to support human civilization. These would need to be designed to handle the harsh Martian environment and would either have to be serviceable whilst wearing an EVA suit or housed inside a human habitable environment. For example, if electricity generation systems rely on solar power, large energy storage facilities will also be needed to cover the periods when dust storms block out the sun, and automatic dust removal systems may be needed to avoid human exposure to conditions on the surface.[29] If the colony is to scale beyond a few people, systems will also need to maximise use of local resources to reduce the need for resupply from Earth, for example by recycling water and oxygen and being adapted to be able to use any water found on Mars, whatever form it is in.

Communications with Earth are relatively straightforward during the half-sol when Earth is above the Martian horizon. NASA and ESA included communications relay equipment in several of the Mars orbiters, so Mars already has communications satellites. While these will eventually wear out, additional orbiters with communication relay capability are likely to be launched before any colonization expeditions are mounted.

The one-way communication delay due to the speed of light ranges from about 3 minutes at closest approach (approximated by perihelion of Mars minus aphelion of Earth) to 22minutes at the largest possible superior conjunction (approximated by aphelion of Mars plus aphelion of Earth). Real-time communication, such as telephone conversations or Internet Relay Chat, between Earth and Mars would be highly impractical due to the long time lags involved. NASA has found that direct communication can be blocked for about two weeks every synodic period, around the time of superior conjunction when the Sun is directly between Mars and Earth,[76] although the actual duration of the communications blackout varies from mission to mission depending on various factorssuch as the amount of link margin designed into the communications system, and the minimum data rate that is acceptable from a mission standpoint. In reality most missions at Mars have had communications blackout periods of the order of a month.[77]

A satellite at the L4 or L5 EarthSun Lagrangian point could serve as a relay during this period to solve the problem; even a constellation of communications satellites would be a minor expense in the context of a full colonization program. However, the size and power of the equipment needed for these distances make the L4 and L5 locations unrealistic for relay stations, and the inherent stability of these regions, although beneficial in terms of station-keeping, also attracts dust and asteroids, which could pose a risk.[78] Despite that concern, the STEREO probes passed through the L4 and L5 regions without damage in late 2009.

Recent work by the University of Strathclyde’s Advanced Space Concepts Laboratory, in collaboration with the European Space Agency, has suggested an alternative relay architecture based on highly non-Keplerian orbits. These are a special kind of orbit produced when continuous low-thrust propulsion, such as that produced from an ion engine or solar sail, modifies the natural trajectory of a spacecraft. Such an orbit would enable continuous communications during solar conjunction by allowing a relay spacecraft to “hover” above Mars, out of the orbital plane of the two planets.[79] Such a relay avoids the problems of satellites stationed at either L4 or L5 by being significantly closer to the surface of Mars while still maintaining continuous communication between the two planets.

The path to a human colony could be prepared by robotic systems such as the Mars Exploration Rovers Spirit, Opportunity and Curiosity. These systems could help locate resources, such as ground water or ice, that would help a colony grow and thrive. The lifetimes of these systems would be years and even decades, and as recent developments in commercial spaceflight have shown, it may be that these systems will involve private as well as government ownership. These robotic systems also have a reduced cost compared with early crewed operations, and have less political risk.

Wired systems might lay the groundwork for early crewed landings and bases, by producing various consumables including fuel, oxidizers, water, and construction materials. Establishing power, communications, shelter, heating, and manufacturing basics can begin with robotic systems, if only as a prelude to crewed operations.

Mars Surveyor 2001 Lander MIP (Mars ISPP Precursor) was to demonstrate manufacture of oxygen from the atmosphere of Mars,[80] and test solar cell technologies and methods of mitigating the effect of Martian dust on the power systems.[81][needs update]

Before any people are transported to Mars on the notional 2030s Interplanetary Transport System envisioned by SpaceX, a number of robotic cargo missions would be undertaken first in order to transport the requisite equipment, habitats and supplies.[82]Equipment that would be necessary would include “machines to produce fertilizer, methane and oxygen from Mars’ atmospheric nitrogen and carbon dioxide and the planet’s subsurface water ice” as well as construction materials to build transparent domes for initial agricultural areas.[83]

As with early colonies in the New World, economics would be a crucial aspect to a colony’s success. The reduced gravity well of Mars and its position in the Solar System may facilitate MarsEarth trade and may provide an economic rationale for continued settlement of the planet. Given its size and resources, this might eventually be a place to grow food and produce equipment to mine the asteroid belt.

A major economic problem is the enormous up-front investment required to establish the colony and perhaps also terraform the planet.

Some early Mars colonies might specialize in developing local resources for Martian consumption, such as water and/or ice. Local resources can also be used in infrastructure construction.[84] One source of Martian ore currently known to be available is metallic iron in the form of nickeliron meteorites. Iron in this form is more easily extracted than from the iron oxides that cover the planet.

Another main inter-Martian trade good during early colonization could be manure.[85] Assuming that life doesn’t exist on Mars, the soil is going to be very poor for growing plants, so manure and other fertilizers will be valued highly in any Martian civilization until the planet changes enough chemically to support growing vegetation on its own.

Solar power is a candidate for power for a Martian colony. Solar insolation (the amount of solar radiation that reaches Mars) is about 42% of that on Earth, since Mars is about 52% farther from the Sun and insolation falls off as the square of distance. But the thin atmosphere would allow almost all of that energy to reach the surface as compared to Earth, where the atmosphere absorbs roughly a quarter of the solar radiation. Sunlight on the surface of Mars would be much like a moderately cloudy day on Earth.[86]

Space colonization on Mars can roughly be said to be possible when the necessary methods of space colonization become cheap enough (such as space access by cheaper launch systems) to meet the cumulative funds that have been gathered for the purpose.

Although there are no immediate prospects for the large amounts of money required for any space colonization to be available given traditional launch costs,[87][full citation needed] there is some prospect of a radical reduction to launch costs in the 2020s, which would consequently lessen the cost of any efforts in that direction. With a published price of US$62 million per launch of up to 22,800kg (50,300lb) payload to low Earth orbit or 4,020kg (8,860lb) to Mars,[88] SpaceX Falcon 9 rockets are already the “cheapest in the industry”.[89] SpaceX’s reusable plans include Falcon Heavy and future methane-based launch vehicles including the Interplanetary Transport System. If SpaceX is successful in developing the reusable technology, it would be expected to “have a major impact on the cost of access to space”, and change the increasingly competitive market in space launch services.[90]

Alternative funding approaches might include the creation of inducement prizes. For example, the 2004 President’s Commission on Implementation of United States Space Exploration Policy suggested that an inducement prize contest should be established, perhaps by government, for the achievement of space colonization. One example provided was offering a prize to the first organization to place humans on the Moon and sustain them for a fixed period before they return to Earth.[91]

Mars Odyssey found what appear to be natural caves near the volcano Arsia Mons. It has been speculated that settlers could benefit from the shelter that these or similar structures could provide from radiation and micrometeoroids. Geothermal energy is also suspected in the equatorial regions.[92]

Several possible Martian lava tube skylights have been located on the flanks of Arsia Mons. Earth based examples indicate that some should have lengthy passages offering complete protection from radiation and be relatively easy to seal using on-site materials, especially in small subsections.[93]

Robotic spacecraft to Mars are required to be sterilized, to have at most 300,000 spores on the exterior of the craftand more thoroughly sterilized if they contact “special regions” containing water,[94][95] otherwise there is a risk of contaminating not only the life-detection experiments but possibly the planet itself.

It is impossible to sterilize human missions to this level, as humans are host to typically a hundred trillion microorganisms of thousands of species of the human microbiome, and these cannot be removed while preserving the life of the human. Containment seems the only option, but it is a major challenge in the event of a hard landing (i.e. crash).[96] There have been several planetary workshops on this issue, but with no final guidelines for a way forward yet.[97] Human explorers would also be vulnerable to back contamination to Earth if they become carriers of microorganisms.[98]

One possible ethical challenge that space travelers might face is that of pregnancy during the trip. According to NASA’s policies, it is forbidden for members of the crew to engage in sex in space. NASA wants its crewmembers to treat each other like coworkers would in a professional environment. A pregnant member on a spacecraft is dangerous to all those aboard. The pregnant woman and child would most likely need additional nutrition from the rations aboard, as well as special treatment and care. At some point during the trip, the pregnancy would most likely impede on the pregnant crew member’s duties and abilities. It is still not fully known how the environment in a spacecraft would affect the development of a child aboard. It is known however that an unborn child in space would be more susceptible to solar radiation, which would likely have a negative effect on its cells and genetics.[99] During a long trip to Mars it is likely that members of craft may engage in sex due to their stressful and isolated environment.[100]

It is unforeseen how the first human landing on Mars will change the current policies regarding the exploration of space and occupancy of celestial bodies. In the 1967, United Nations Treaty on Principles Governing the Activities of States in the Exploration and Use of Outer Space, Including the Moon and Other Celestial Bodies, it was determined that no country may take claim to space or its inhabitants. Since the planet Mars offers a challenging environment and dangerous obstacles for humans to overcome, the laws and culture on the planet will most likely be very different from those on Earth.[101] With Elon Musk announcing his plans for travel to Mars, it is uncertain how the dynamic of a private company possibly being the first to put a human on Mars will play out on a national and global scale.[102][103] NASA had to deal with several cuts in funding. During the presidency of Barack Obama, the objective for NASA to reach Mars was pushed to the background.[104] In 2017, president Donald Trump promised to return humans to the Moon and eventually Mars,[105] effectively taking action by increasing NASA budget with $1.1 billion,[106] and mostly focus on the development of the new Space Launch System.[107][108]

Mars colonization is advocated by several non-governmental groups for a range of reasons and with varied proposals. One of the oldest groups is the Mars Society who promote a NASA program to accomplish human exploration of Mars and have set up Mars analog research stations in Canada and the United States. Mars to Stay advocates recycling emergency return vehicles into permanent settlements as soon as initial explorers determine permanent habitation is possible. Mars One, which went public in June2012, aims to coordinate -not build- a human colony on Mars by 2027 with funding coming from a reality TV show and other commercial exploitation, although this approach has been widely criticized as unrealistic and infeasible.[109][110][111]

Elon Musk founded SpaceX with the long-term goal of developing the technologies that will enable a self-sustaining human colony on Mars.[102][112] In 2015 he stated “I think we’ve got a decent shot of sending a person to Mars in 11 or 12years”.[113] Richard Branson, in his lifetime, is “determined to be a part of starting a population on Mars. I think it is absolutely realistic. It will happen… I think over the next 20 years, we will take literally hundreds of thousands of people to space and that will give us the financial resources to do even bigger things”.[114]

In June 2013, Buzz Aldrin, American engineer and former astronaut, and the second person to walk on the Moon, wrote an opinion, published in The New York Times, supporting a human mission to Mars and viewing the Moon “not as a destination but more a point of departure, one that places humankind on a trajectory to homestead Mars and become a two-planet species.”[115] In August 2015, Aldrin, in association with the Florida Institute of Technology, presented a “master plan”, for NASA consideration, for astronauts, with a “tour of duty of ten years”, to colonize Mars before the year 2040.[116]

A few instances in fiction provide detailed descriptions of Mars colonization. They include:

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Colonization of Mars – Wikipedia

Minerva Reefs – Wikipedia

The Minerva Reefs (Tongan: Ongo Teleki) are a group of two mostly submerged atolls located in the Pacific Ocean south of Fiji and Tonga.

The reefs were named after the whaleship Minerva, wrecked on what became known as South Minerva after setting out from Sydney in 1829. Many other ships would follow, for example Strathcona, which was sailing north soon after completion in Auckland in 1914. In both cases most of the crew saved themselves in whaleboats or rafts and reached the Lau Islands in Fiji.[citation needed]

The reefs were first discovered by Captain John Nicholson of LMS Haweis in December 1818 as reported in the Sydney Gazette 30 January 1819.[1] Captain H. M. Denham of HMSHerald surveyed the reefs in 1854 and renamed them after the Australian whaler Minerva which ran aground on South Minerva Reef on 9 September 1829.[2][3]

In 1972, Lithuanian-born real-estate millionaire Michael Oliver, of the Phoenix Foundation, sought to establish a libertarian country on the reefs. Oliver formed a syndicate, the Ocean Life Research Foundation, which allegedly had some $100,000,000 for the project and had offices in New York City and London.[citation needed] In 1971, barges loaded with sand arrived from Australia, bringing the reef levelnormally a metre below sea level at high tide[citation needed]above water. In 1972, the Phoenix Foundation began constructing a platform on the Minerva Reefs. The Republic of Minerva issued a “declaration of independence” on 19 January 1972 in letters to neighboring countries and began minting their own currency. In February 1972, Morris C. Davis was elected as “Provisional President” of the Republic of Minerva.[citation needed]

Tongas claim to the reef was recognized by the South Pacific Forum in September 1972. A Tongan expedition was sent to enforce the claim, arriving on 18 June 1972. The Flag of the Tonga was raised on 19 June 1972 on North Minerva and on South Minerva on 21 June 1972.[4][5]

In 1982, a group of Americans led again by Morris C. Bud Davis tried to occupy the reefs, but were forced off by Tongan troops after three weeks.[citation needed] According to Reason, Minerva has been “more or less reclaimed by the sea”.[6]

In 2005, Fiji declared that it did not recognize any maritime water claims by Tonga to the Minerva Reefs under the UNCLOS agreements. In November 2005, Fiji lodged a complaint with the International Seabed Authority concerning Tonga’s maritime waters claims surrounding Minerva. Tonga lodged a counter claim. In 2010 the Fijian Navy destroyed navigation lights at the entrance to the lagoon. In late May 2011, they again destroyed navigational equipment installed by Tongans. In early June 2011, two Royal Tongan Navy ships were sent to the reef to replace the equipment, and to reassert Tonga’s claim to the territory. Fijian Navy ships in the vicinity reportedly withdrew as the Tongans approached.[7][8]

In an effort to settle the dispute, the government of Tonga revealed a proposal in early July 2014 to give the Minerva Reefs to Fiji in exchange for the Lau Group of islands.[9] In a statement to the Tonga Daily News, Lands Minister Lord Maafu Tukuiaulahi announced that he would make the proposal to Fiji’s Minister for Foreign Affairs, Ratu Inoke Kubuabola. Some Tongans have Lauan ancestors and many Lauans have Tongan ancestors; Tonga’s Lands Minister is named after Enele Ma’afu, the Tongan Prince who originally claimed parts of Lau for Tonga.[10]

Area: North Reef diameter about 5.6 kilometres (3.5mi), South Reef diameter of about 4.8 kilometres (3.0mi).Terrain: two (atolls) on dormant volcanic seamounts.

Both Minerva Reefs are about 435 kilometres (270mi) southwest of the Tongatapu Group.The atolls are on a common submarine platform from 549 to 1,097 metres (1,801 to 3,599ft) below the surface of the sea. North Minerva is circular in shape and has a diameter of about 5.6 kilometres (3.5mi). There is a small sand bar around the atoll, awash at high tide, with a small entrance into the flat lagoon with a somewhat deep harbor. South Minerva is parted into The East Reef and the West Reef, both circular with a diameter of about 4.8 kilometres (3.0mi). Remnants of shipwrecks and platforms remain on the atolls, plus functioning navigation beacons.

Geologically, Minerva Reef is of a limestone base formed from uplifted coral formations elevated by now-dormant volcanic activity.

The climate is basically subtropical with a distinct warm period (DecemberApril), during which the temperatures rise above 32C (90F), and a cooler period (MayNovember), with temperatures rarely rising above 27C (80F). The temperature increases from 23C to 27C (74F to 80F), and the annual rainfall is from 170 to 297 centimeters (67117 in.) as one moves from Cardea in the south to the more northerly islands closer to the Equator. The mean daily humidity is 80percent.

Both North and South Minerva Reefs are used as anchorages by private yachts traveling between New Zealand and Tonga or Fiji.[11] North Minerva (Tongan: Teleki Tokelau) offers the more protected anchorage, with a single, easily negotiated, west-facing pass that offers access to the large, calm lagoon with extensive sandy areas. South Minerva (Tongan: Teleki Tonga) is in shape similar to an infinity symbol, with its eastern lobe partially open to the ocean on the northern side.

On July 7 1962 the Tuaikaepau (‘Slow But Sure’), a Tongan vessel on its way to New Zealand, struck the reefs.[12] This 15-metre (49ft) wooden vessel was built in 1902 at the same yard as the Strathcona. The crew and passengers survived by living in the remains of a Japanese freighter. There they remained for three months and several died. Without tools, Captain Tvita Fifita built a small boat using wood recovered from the ship. With this raft, named Malolelei (‘Good Day’), he and several others sailed to Fiji in one week.

Coordinates: 2338S 17854W / 23.633S 178.900W / -23.633; -178.900

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Minerva Reefs – Wikipedia

Chesterfield Islands – Wikipedia

Chesterfield Islands (les Chesterfield in French) are a French archipelago of New Caledonia located in the Coral Sea, 550km northwest of Grande Terre, the main island of New Caledonia. The archipelago is 120km long and 70km broad, made up of 11 uninhabited islets and many reefs. The land area of the islands is less than 10km.[citation needed]

During periods of lowered sea level during the Pleistocene ice ages an island of considerable size (Greater Chesterfield Island) occupied the location of the archipelago.

Bellona Reef, 164km south-southeast of Chesterfield, is geologically separated from the Chesterfield archipelago but commonly included.

The reef complex is named after the ship Chesterfield, commanded by Matthew Bowes Alt, which explored the Coral Sea in the 1790s.[1]

The Chesterfield Islands, sometimes referred to as the Chesterfield Reefs or Chesterfield Group, are the most important of a number of uninhabited coral sand cays. Some are awash and liable to shift with the wind while others are stabilized by the growth of grass, creepers and low trees. The reefs extend from 19 to 22S between 158160E in the southern Coral Sea halfway between Australia and New Caledonia. The Chesterfield Reefs are now part of the territory of New Caledonia while the islands farther west are part of the Australian Coral Sea Islands Territory.

Chesterfield lagoon, located between 1900′ and 2030′ S and 15810′ and 159E covers an area of approximately 3500km2. A barrier reef surrounds the lagoon, interrupted by wide passes except on its eastern side where it is open for over 20 nautical miles (37km). The major part of the lagoon is exposed to trade winds and to the southeastern oceanic swell. The lagoon is relatively deep with a mean depth of 51 m. The depth increases from south to north.[2]

Chesterfield Reefs complex consists of the Bellona Reef complex to the south (South, Middle and Northwest Bellona Reef) and the Bampton Reef complex.

Captain Matthew Boyd of Bellona named the reefs for his ship. He had delivered convicts to New South Wales in 1793 and was on his way to China to pick up a cargo at Canton to take back to Britain for the British East India Company when he passed the reefs in FebruaryMarch 1793.

Lieutenant John Lamb, R.N., Commander of the ship Baring, spent three days in the neighborhood of Booby and Bellona Shoals and reefs. Lamb took soundings between nineteen and forty-five fathoms (114270ft), and frequently passed shoals, upon which the sea was breaking. Lamb defined the limits of the rocky ground as the parallels of 2040 and 2150 and the meridians of 15815 and 15930. He also saw a sandy islet, surrounded by a chain of rocks, at 2124 south and 15830 east. The ship Minerva measured the water’s depth as eight fathoms (48ft), with the appearance of shallower water to the southwest; this last danger is in a line between the two shoals at about longitude 15920 east, as described by James Horsburgh.[3]

Observatory Cay (Caye de l’Observatoire) 2124S 15851E / 21.400S 158.850E / -21.400; 158.850 (Bellona Reefs – Observatory Cay), 800 m long and 2 m high, lies on the Middle Bellona Reefs at the southern end of the Chesterfield Reefs and 180nm east of Kenn Reef.

The Chesterfield Reefs is a loose collection of elongated reefs that enclose a deep, semi-sheltered, lagoon. The reefs on the west and northwest are known as the Chesterfield Reefs; those on the east and north being the Bampton Reefs. The Chesterfield Reefs form a structure measuring 120km in length (northeast to southwest) and 70km across (east to west).

There are numerous cays occurring amongst the reefs of both the Chesterfield and Bampton Reefs. These include: Loop Islet, Renard Cay, Skeleton Cay, Bennett Island, Passage Islet, Long Island, the Avon Isles, the Anchorage Islets and Bampton Island.

Long Island 1953S 15819E / 19.883S 158.317E / -19.883; 158.317 (Chesterfield Reefs – Long Island), 10nm NW of Loop Islet, is the largest of the Chesterfield Islands, and is 1400 to 1800 m long but no more than 100 m across and 9 m high. In May 1859 Henry Mangles Denham found Long Island was a heap of ‘foraminifera’ densely covered with stunted bushtrees with leaves as large as cabbage plants, spreading 12 feet (3.7 m) and reaching as high, upon trunks 9 inches (23cm) diameter… The trees around the margin of this island were leafless, as if from the seafowl.”[citation needed] Although wooded in the 1850s, it was stripped during guano extraction in the 1870s and was said to be covered in grass with only two coconut trees and some ruins at the south end early in the 20th century. The vegetation was growing again by 1957 when the remaining ruins were confused with those of a temporary automatic meteorological station established in the same area by the Americans between 1944 and 1948. Terry Walker reported that by 1990 there was a ring of low Tournefortia trees growing around the margin, herbs, grass and shrubs in the interior, and still a few exotic species including coconuts.

South of Long Island and Loop Islet there are three small low islets up to 400 m across followed, after a narrow channel, by Passage or Bennett Island, which is 12 m high and was a whaling station in the first half of the 20th century. Several sand cays lie on the reef southeast of the islet.

The two Avon Isles 1932S 15815E / 19.533S 158.250E / -19.533; 158.250 (Avon Isles), some 188 m in diameter and 5 m high to the top of the dense vegetation, are situated 21 n.m. north of Long Island. They were seen by Mr. Sumner, Master of the ship Avon, on 18 September 1823, and are described by him as being three-quarters of a mile in circumference, twenty feet high, and the sea between them twenty fathoms deep. At four miles (7km) northeast by north from them the water was twelve fathoms (72 feet) deep, and at the same time they saw a reef ten or fifteen miles (2030km) to the southeast, with deep water between it and the islets. A boat landed on the south-westernmost islet, and found it inhabited only by birds, but clothed with shrubs and wild grapes. By observation, these islands were found to lie in latitude 19 degrees 40 minutes, and longitude 158 degrees 6 minutes. The Avon Isles are described by Denham in 1859 as densely covered with stunted trees and creeping plants and grass, and… crowded with the like species of birds.”[citation needed]

Renard Island North Bampton Reef 1914S 15858E / 19.233S 158.967E / -19.233; 158.967 (Bampton Reefs – Renard Island), Approximately 6m (20ft) tall sand islet lies 45nmi (83km) northeast of the Avon Isles and is 273m (896ft) long, 180m (590ft) across and also 6m (20ft) high to the top of the bushes.

Southeast Bampton Reef 1908S 15840E / 19.133S 158.667E / -19.133; 158.667 (Southeast Bampton Reef) Sand Cay 5m (16ft) elevation

Loop Islet 1959S 15828E / 19.983S 158.467E / -19.983; 158.467 (Loop Islet), which lies 85nm farther north near the south end of the central islands of Chesterfield Reefs, is a small, flat, bushy islet 3 m high where a permanent automatic weather station was established by the Service Mtorologique de Nouma in October 1968. Terry Walker reported the presence of a grove of Casuarinas in 1990.

Anchorage Islets are a group of islets five nautical miles (9km) north of Loop Islet. The third from the north, about 400 m long and 12 m high, shelters the best anchorage.

Passage (Bonnet) Island reaches a vegetative height of 12 m

Bampton Island 1907S 15836E / 19.117S 158.600E / -19.117; 158.600 (Bampton Island), lies on Bampton Reefs 20nm NW of Renard Island. It is 180 m long, 110 m across and 5 m high. It had trees when discovered in 1793, but has seldom been visited since then except by castaways.

The reefs and islands west of the Chesterfield Islands, the closest being Mellish Reef with Herald’s Beacon Islet at 1725S 15552E / 17.417S 155.867E / -17.417; 155.867 (Herald’s Beacon Islet), at a distance of 180 nm northwest of Bampton Island, belong to the Coral Sea Islands Territory.

Booby Reef in the center of the eastern chain of reefs and islets comprising Chesterfield Reefs appears to have been discovered first by Lt. Henry Lidgbird Ball in HMS Supply on the way from Sydney to Batavia (modern day Jakarta) in 1790. The reefs to the south were found next by Mathew Boyd in the convict ship Bellona on his way from Sydney to Canton (modern day Guangzhou) in February or March 1793.[4] The following June, William Wright Bampton became embayed for five days at the north end of Chesterfield Reefs in the Indiaman Shah Hormuzeer, together with Mathew Bowes Alt in the whaler Chesterfield.[5] Bampton reported two islets with trees and a number of birds of different species around the ships, several of them the same kind as at Norfolk Island.[6]

The reefs continued to present a hazard to shipping plying between Australia and Canton or India (where cargo was collected on the way home to Europe). The southern reefs were surveyed by Captain Henry Mangles Denham in the Herald from 1858 to 1860.[7] He made the natural history notes discussed below. The northern reefs were charted by Lieutenant G.E.Richards in HMS Renard in 1878 and the French the following year. Denham’s conclusions are engraved on British Admiralty Chart 349:

These Plans and a masthead Lookout will enable a Ship to round to under the lee of the Reefs where she may caulk topsides, set up rigging, rate Chronometers, [and] obtain turtle, fish and seafowl eggs. On some of the more salient reefs, beacons were erected by Capt. Denham, and for the sake of castaways, cocoanuts, shrubs, grasses & every description of seed likely to grow, were sown in the way to promote the superstructure; and it is most desirable that these Refuge spots should be held sacred for universal benefit and not ruthlessly destroyed by the Guanoseeker.[8]

The area is a wintering ground for numerous Humpback whales and smaller numbers of Sperm whales. During the 19th century the Chesterfield Islands were visited by increasing numbers of whalers during the off season in New Zealand. L. Thiercelin reported that in July 1863 the islets only had two or three plants, including a bush 34 m high, and were frequented by turtles weighing 60 to 100kg.[9] Many eggs were being taken regularly by several English, two French and one American whaler. On another occasion there were no less than eight American whalers.[10] A collection of birds said to have been made by Surgeon Jourde of the French whaler Gnral dHautpoul on the Brampton Shoals in July 1861 was subsequently brought by Gerard Krefft (1862) to the Australian Museum, but clearly not all the specimens came from there.

On 27 October 1862, the British Government granted an exclusive concession to exploit the guano on Lady Elliot Island, Wreck Reef, Swain Reefs, Raine Island, Bramble Cay, Brampton Shoal, and Pilgrim Island to the Anglo Australian Guano Company organized by the whaler Dr. William Crowther in Hobart, Tasmania. They were apparently most active on Bird Islet (Wreck Reef) and Lady Elliot and Raine Islands (Hutchinson, 1950),[citation needed] losing five ships at Bird Islet between 1861 and 1882 (Crowther 1939).[citation needed] It is not clear that they ever took much guano from the Chesterfield Islands unless it was obtained from Higginson, Desmazures et Cie, discussed below.

When in 1877 Joshua William North also found guano on the Chesterfield Reefs, Alcide Jean Desmazures persuaded Governor Orly of New Caledonia to send the warship La Seudre to annex them. There were estimated to be about 185,000 cu m of guano on Long Island and a few hundred tons elsewhere, and 40% to 62% phosphate (Chevron, 1880),[citation needed] which was extracted between 1879 and 1888 by Higginson, Desmazures et Cie of Nouma (Godard, nd),[citation needed] leaving Long Island stripped bare for a time (Anon., 1916).[citation needed]

Apparently the islands were then abandoned until Commander Arzur in the French warship Dumont dUrville surveyed the Chesterfield Reefs and erected a plaque in 1939. In September 1944, American forces installed a temporary automatic meteorological station at the south end of Long Island, which was abandoned again at the end of World War II. The first biological survey was made of Long Island by Cohic during four hours ashore on 26 September 1957.[11] It revealed, among other things, a variety of avian parasites including a widespread Ornithodoros tick belonging to a genus carrying arboviruses capable of causing illness in humans. This island and the Anchorage Islets were also visited briefly during a survey of New Caledonian coral reefs in 1960 and 1962.

An aerial magnetic survey was made of the Chesterfield area in 1966, and a seismic survey in 1972, which apparently have not been followed up yet. In November 1968 another automatic meteorological station was installed on Loop Islet where 10 plants were collected by A.E. Ferr.[citation needed] Since then the Centre de Nouma of the Office de la Recherche Scientifique et Technique Outre Mer has arranged for periodic surveys and others when this installation is serviced.

From 1982-1992 Terry Walker carried out methodical surveys of the Coral Sea islets with the intention of producing a seabird atlas. He visited the central islands of the Chesterfield Reefs in December 1990.[12]

An amateur radio DX-pedition (TX3X) was conducted on one of the islands in October 2015.

Unless otherwise noted, information in this section is from Coral Sea and Northern Great Barrier Reef Shipwrecks.[13]

Coordinates: 1921S 15840E / 19.350S 158.667E / -19.350; 158.667

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Chesterfield Islands – Wikipedia

A list of Caribbean Shipwrecks | Pirate Shipwrecks …

The following is a list of shipwrecks that have been found. Some are old some are new.

Bahamas* SS Sapona a cargo steamer run aground near Bimini during a hurricane in 1926.

Bermuda* Sea Venture grounded off the coast in 1609, subsequently broke up and sank.* Warwick English cargo ship sunk in a gale in Castle Harbor in 1619, discovered in 1967.* San Antonio Portuguese nao wrecked on the west reefs in 1621, discovered in 1960.* Eagle Virginia Company ship wrecked in 1659.* Virginia Merchant Virginia Company ship wrecked in 1661.* Unidentified ship wrecked around 1750, found in 1983, known as the Frenchman wreck.* Unidentified ship wrecked mid-18th century, known as the Manilla wreck.* Hunters Galley wrecked in 1752.* Katherine wrecked in 1763.* Mark Antonio Spanish privateer, wrecked in 1777, discovered early 1960s.* Lord Amherst British armed transport wrecked in 1778.* HMS Cerberus lost at Castle Harbor in 1783.* HMS Pallas ran aground in 1783 off St. Georges Island, wreck has not been identified.* Caesar wrecked on a reef in 1818 en route from England to Baltimore.* Collector wrecked in 1823.* LHerminie French frigate wrecked in 1838.* Unidentified ship wrecked in 1849, believed to be the Minerva though that ship was wrecked in 1795.* Curlew wrecked on the northern reefs in 1856.* Montana American Civil War blockade runner sank in 1863.* Mari Celeste American Civil War blockade runner being piloted by a Bermudian, sank in eight minutes in 1864.* Beaumaris Castle ran aground in 1873.* Minnie Breslauer ran aground in 1873.* Alert fishing sloop sank in 1877.* Kate British steamer wrecked in 1878.* Lartington wrecked in 1879 after just five years of operation.* North Carolina wrecked off West End in 1880.* Darlington wrecked on the Western Reef in 1886.* Richard P. Buck caught fire and sank following a storm in 1889.* Apollo wrecked on the reefs in 1890.* Avenger wrecked on Mills Breakers in 1894.* HMS Vixen scuttled in 1896.* Madiana former Balmoral Castle, built 1877, wrecked 1903* Pollockshields former Herodot, wrecked in 1915 near Elbow Beach.* Blanch King wrecked on the southwest reefs in 1920.* Taunton Norwegian steamer wrecked on the northern reefs in 1920.* Caraquet mail steamer wrecked on the northern barrier reef in 1923.* Zovetto cargo steamer ran aground in 1924, also known as Zovetta or Rita Zovetto.* Mussel Bermudian fishing boat wrecked in 1926.* Cristobal Colon Bermudas largest shipwreck sank in 1936.* Iristo Norwegian steamer also known as Aristo, grounded in 1937 after mistaking the Colon wreck for a ship still underway.* Pelinaion Greek steamer wrecked in 1940.* Constellation made famous in The Deep, sank in 1942.* Colonel William G. Ball wrecked on Mills Breakers in severe weather in 1943.* Wychwood ran aground in 1955, refloated, then sank again.* Elda wrecked in 1956 near the Eagle wreck.* Ramona Canadian ship wrecked in 1967, refloated for salvaging, re-sunk near Dockyard.* King American ship scuttled in 1984, first intentionally-created dive site in Bermuda.* Hermes American ship deliberately scuttled in 1984.* Triton scuttled in 1988 as a dive site.

British Virgin Islands* HMS Astraea a British frigate wrecked off the coast of Anegada on 23 May 1808.* HMS Nymph a British sloop caught fire, foundered and sank in Road Towns harbour in 1783.* RMS Rhone a British packet ship wrecked during a hurricane off the coast of Salt Island on 29 October 1867.

Dominican Republic* Nuestra Seora de Guadalupe a Spanish galleon sunk by hurricane in Samana Bay on 24 August 1724.* Conde de Tolosa a Spanish galleon run aground during a hurricane in Samana Bay on 25 August 1724.* St. George sunk as an artificial reef near La Romana in 1999.* Astron a freighter scuttled just off the coast of Punta Cana.* Monte Cristi Pipe Wreck sunk off the north coast of the Dominican Republic in the later part of the 17th century.* La Viete, French merchant ship, lost on a voyage of reinforcement and supply with a demi-brigade of artillery and infantry, their equipment, and a large shipment of specie (coins), etc. in 1802. This may be the wreck discovered by North Caribbean Research S.A. off Punta Luna. The Punta Luna wreck project is directed by NCRs Rick Berry.

Grenada* Bianca C a passenger ship sunk multiple times before becoming the Caribbeans largest shipwreck, near Grand Anse, in October 1961.

Haiti* Bluenose a Canadian schooner foundered on a reef on 28 January 1946.

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A list of Caribbean Shipwrecks | Pirate Shipwrecks …

Human genetics | biology | Britannica.com

Human genetics, study of the inheritance of characteristics by children from parents. Inheritance in humans does not differ in any fundamental way from that in other organisms.

The study of human heredity occupies a central position in genetics. Much of this interest stems from a basic desire to know who humans are and why they are as they are. At a more practical level, an understanding of human heredity is of critical importance in the prediction, diagnosis, and treatment of diseases that have a genetic component. The quest to determine the genetic basis of human health has given rise to the field of medical genetics. In general, medicine has given focus and purpose to human genetics, so the terms medical genetics and human genetics are often considered synonymous.

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genetics: Human genetics

Some geneticists specialize in the hereditary processes of human genetics. Most of the emphasis is on understanding and treating genetic disease and genetically influenced ill health, areas collectively known as medical genetics. One broad area of activity is laboratory research dealing with the

A new era in cytogenetics, the field of investigation concerned with studies of the chromosomes, began in 1956 with the discovery by Jo Hin Tjio and Albert Levan that human somatic cells contain 23 pairs of chromosomes. Since that time the field has advanced with amazing rapidity and has demonstrated that human chromosome aberrations rank as major causes of fetal death and of tragic human diseases, many of which are accompanied by mental retardation. Since the chromosomes can be delineated only during mitosis, it is necessary to examine material in which there are many dividing cells. This can usually be accomplished by culturing cells from the blood or skin, since only the bone marrow cells (not readily sampled except during serious bone marrow disease such as leukemia) have sufficient mitoses in the absence of artificial culture. After growth, the cells are fixed on slides and then stained with a variety of DNA-specific stains that permit the delineation and identification of the chromosomes. The Denver system of chromosome classification, established in 1959, identified the chromosomes by their length and the position of the centromeres. Since then the method has been improved by the use of special staining techniques that impart unique light and dark bands to each chromosome. These bands permit the identification of chromosomal regions that are duplicated, missing, or transposed to other chromosomes.

Micrographs showing the karyotypes (i.e., the physical appearance of the chromosome) of a male and a female have been produced. In a typical micrograph the 46 human chromosomes (the diploid number) are arranged in homologous pairs, each consisting of one maternally derived and one paternally derived member. The chromosomes are all numbered except for the X and the Y chromosomes, which are the sex chromosomes. In humans, as in all mammals, the normal female has two X chromosomes and the normal male has one X chromosome and one Y chromosome. The female is thus the homogametic sex, as all her gametes normally have one X chromosome. The male is heterogametic, as he produces two types of gametesone type containing an X chromosome and the other containing a Y chromosome. There is good evidence that the Y chromosome in humans, unlike that in Drosophila, is necessary (but not sufficient) for maleness.

A human individual arises through the union of two cells, an egg from the mother and a sperm from the father. Human egg cells are barely visible to the naked eye. They are shed, usually one at a time, from the ovary into the oviducts (fallopian tubes), through which they pass into the uterus. Fertilization, the penetration of an egg by a sperm, occurs in the oviducts. This is the main event of sexual reproduction and determines the genetic constitution of the new individual.

Human sex determination is a genetic process that depends basically on the presence of the Y chromosome in the fertilized egg. This chromosome stimulates a change in the undifferentiated gonad into that of the male (a testicle). The gonadal action of the Y chromosome is mediated by a gene located near the centromere; this gene codes for the production of a cell surface molecule called the H-Y antigen. Further development of the anatomic structures, both internal and external, that are associated with maleness is controlled by hormones produced by the testicle. The sex of an individual can be thought of in three different contexts: chromosomal sex, gonadal sex, and anatomic sex. Discrepancies between these, especially the latter two, result in the development of individuals with ambiguous sex, often called hermaphrodites. The phenomenon of homosexuality is of uncertain cause and is unrelated to the above sex-determining factors. It is of interest that in the absence of a male gonad (testicle) the internal and external sex anatomy is always female, even in the absence of a female ovary. A female without ovaries will, of course, be infertile and will not experience any of the female developmental changes normally associated with puberty. Such a female will often have Turners syndrome.

If X-containing and Y-containing sperm are produced in equal numbers, then according to simple chance one would expect the sex ratio at conception (fertilization) to be half boys and half girls, or 1 : 1. Direct observation of sex ratios among newly fertilized human eggs is not yet feasible, and sex-ratio data are usually collected at the time of birth. In almost all human populations of newborns, there is a slight excess of males; about 106 boys are born for every100 girls. Throughout life, however, there is a slightly greater mortality of males; this slowly alters the sex ratio until, beyond the age of about 50 years, there is an excess of females. Studies indicate that male embryos suffer a relatively greater degree of prenatal mortality, so the sex ratio at conception might be expected to favour males even more than the 106 : 100 ratio observed at birth would suggest. Firm explanations for the apparent excess of male conceptions have not been established; it is possible that Y-containing sperm survive better within the female reproductive tract, or they may be a little more successful in reaching the egg in order to fertilize it. In any case, the sex differences are small, the statistical expectation for a boy (or girl) at any single birth still being close to one out of two.

During gestationthe period of nine months between fertilization and the birth of the infanta remarkable series of developmental changes occur. Through the process of mitosis, the total number of cells changes from 1 (the fertilized egg) to about 2 1011. In addition, these cells differentiate into hundreds of different types with specific functions (liver cells, nerve cells, muscle cells, etc.). A multitude of regulatory processes, both genetically and environmentally controlled, accomplish this differentiation. Elucidation of the exquisite timing of these processes remains one of the great challenges of human biology.

Immunity is the ability of an individual to recognize the self molecules that make up ones own body and to distinguish them from such nonself molecules as those found in infectious microorganisms and toxins. This process has a prominent genetic component. Knowledge of the genetic and molecular basis of the mammalian immune system has increased in parallel with the explosive advances made in somatic cell and molecular genetics.

There are two major components of the immune system, both originating from the same precursor stem cells. The bursa component provides B lymphocytes, a class of white blood cells that, when appropriately stimulated, differentiate into plasma cells. These latter cells produce circulating soluble proteins called antibodies or immunoglobulins. Antibodies are produced in response to substances called antigens, most of which are foreign proteins or polysaccharides. An antibody molecule can recognize a specific antigen, combine with it, and initiate its destruction. This so-called humoral immunity is accomplished through a complicated series of interactions with other molecules and cells; some of these interactions are mediated by another group of lymphocytes, the T lymphocytes, which are derived from the thymus gland. Once a B lymphocyte has been exposed to a specific antigen, it remembers the contact so that future exposure will cause an accelerated and magnified immune reaction. This is a manifestation of what has been called immunological memory.

The thymus component of the immune system centres on the thymus-derived T lymphocytes. In addition to regulating the B cells in producing humoral immunity, the T cells also directly attack cells that display foreign antigens. This process, called cellular immunity, is of great importance in protecting the body against a variety of viruses as well as cancer cells. Cellular immunity is also the chief cause of the rejection of organ transplants. The T lymphocytes provide a complex network consisting of a series of helper cells (which are antigen-specific), amplifier cells, suppressor cells, and cytotoxic (killer) cells, all of which are important in immune regulation.

One of the central problems in understanding the genetics of the immune system has been in explaining the genetic regulation of antibody production. Immunobiologists have demonstrated that the system can produce well over one million specific antibodies, each corresponding to a particular antigen. It would be difficult to envisage that each antibody is encoded by a separate gene; such an arrangement would require a disproportionate share of the entire human genome. Recombinant DNA analysis has illuminated the mechanisms by which a limited number of immunoglobulin genes can encode this vast number of antibodies.

Each antibody molecule consists of several different polypeptide chainsthe light chains (L) and the longer heavy chains (H). The latter determine to which of five different classes (IgM, IgG, IgA, IgD, or IgE) an immunoglobulin belongs. Both the L and H chains are unique among proteins in that they contain constant and variable parts. The constant parts have relatively identical amino acid sequences in any given antibody. The variable parts, on the other hand, have different amino acid sequences in each antibody molecule. It is the variable parts, then, that determine the specificity of the antibody.

Recombinant DNA studies of immunoglobulin genes in mice have revealed that the light-chain genes are encoded in four separate parts in germ-line DNA: a leader segment (L), a variable segment (V), a joining segment (J), and a constant segment (C). These segments are widely separated in the DNA of an embryonic cell, but in a mature B lymphocyte they are found in relative proximity (albeit separated by introns). The mouse has more than 200 light-chain variable region genes, only one of which will be incorporated into the proximal sequence that codes for the antibody production in a given B lymphocyte. Antibody diversity is greatly enhanced by this system, as the V and J segments rearrange and assort randomly in each B-lymphocyte precursor cell. The mechanisms by which this DNA rearrangement takes place are not clear, but transposons are undoubtedly involved. Similar combinatorial processes take place in the genes that code for the heavy chains; furthermore, both the light-chain and heavy-chain genes can undergo somatic mutations to create new antibody-coding sequences. The net effect of these combinatorial and mutational processes enables the coding of millions of specific antibody molecules from a limited number of genes. It should be stressed, however, that each B lymphocyte can produce only one antibody. It is the B lymphocyte population as a whole that produces the tremendous variety of antibodies in humans and other mammals.

Plasma cell tumours (myelomas) have made it possible to study individual antibodies, since these tumours, which are descendants of a single plasma cell, produce one antibody in abundance. Another method of obtaining large amounts of a specific antibody is by fusing a B lymphocyte with a rapidly growing cancer cell. The resultant hybrid cell, known as a hybridoma, multiplies rapidly in culture. Since the antibodies obtained from hybridomas are produced by clones derived from a single lymphocyte, they are called monoclonal antibodies.

As has been stated, cellular immunity is mediated by T lymphocytes that can recognize infected body cells, cancer cells, and the cells of a foreign transplant. The control of cellular immune reactions is provided by a linked group of genes, known as the major histocompatibility complex (MHC). These genes code for the major histocompatibility antigens, which are found on the surface of almost all nucleated somatic cells. The major histocompatibility antigens were first discovered on the leukocytes (white blood cells) and are therefore usually referred to as the HLA (human leukocyte group A) antigens.

The advent of the transplantation of human organs in the 1950s made the question of tissue compatibility between donor and recipient of vital importance, and it was in this context that the HLA antigens and the MHC were elucidated. Investigators found that the MHC resides on the short arm of chromosome 6, on four closely associated sites designated HLA-A, HLA-B, HLA-C, and HLA-D. Each locus is highly polymorphic; i.e., each is represented by a great many alleles within the human gene pool. These alleles, like those of the ABO blood group system, are expressed in codominant fashion. Because of the large number of alleles at each HLA locus, there is an extremely low probability of any two individuals (other than siblings) having identical HLA genotypes. (Since a person inherits one chromosome 6 from each parent, siblings have a 25 percent probability of having received the same paternal and maternal chromosomes 6 and thus of being HLA matched.)

Although HLA antigens are largely responsible for the rejection of organ transplants, it is obvious that the MHC did not evolve to prevent the transfer of organs from one person to another. Indeed, information obtained from the histocompatibility complex in the mouse (which is very similar in its genetic organization to that of the human) suggests that a primary function of the HLA antigens is to regulate the number of specific cytotoxic T killer cells, which have the ability to destroy virus-infected cells and cancer cells.

More is known about the genetics of the blood than about any other human tissue. One reason for this is that blood samples can be easily secured and subjected to biochemical analysis without harm or major discomfort to the person being tested. Perhaps a more cogent reason is that many chemical properties of human blood display relatively simple patterns of inheritance.

Certain chemical substances within the red blood cells (such as the ABO and MN substances noted above) may serve as antigens. When cells that contain specific antigens are introduced into the body of an experimental animal such as a rabbit, the animal responds by producing antibodies in its own blood.

In addition to the ABO and MN systems, geneticists have identified about 14 blood-type gene systems associated with other chromosomal locations. The best known of these is the Rh system. The Rh antigens are of particular importance in human medicine. Curiously, however, their existence was discovered in monkeys. When blood from the rhesus monkey (hence the designation Rh) is injected into rabbits, the rabbits produce so-called Rh antibodies that will agglutinate not only the red blood cells of the monkey but the cells of a large proportion of human beings as well. Some people (Rh-negative individuals), however, lack the Rh antigen; the proportion of such persons varies from one human population to another. Akin to data concerning the ABO system, the evidence for Rh genes indicates that only a single chromosome locus (called r) is involved and is located on chromosome 1. At least 35 Rh alleles are known for the r location; basically the Rh-negative condition is recessive.

A medical problem may arise when a woman who is Rh-negative carries a fetus that is Rh-positive. The first such child may have no difficulty, but later similar pregnancies may produce severely anemic newborn infants. Exposure to the red blood cells of the first Rh-positive fetus appears to immunize the Rh-negative mother, that is, she develops antibodies that may produce permanent (sometimes fatal) brain damage in any subsequent Rh-positive fetus. Damage arises from the scarcity of oxygen reaching the fetal brain because of the severe destruction of red blood cells. Measures are available for avoiding the severe effects of Rh incompatibility by transfusions to the fetus within the uterus; however, genetic counselling before conception is helpful so that the mother can receive Rh immunoglobulin immediately after her first and any subsequent pregnancies involving an Rh-positive fetus. This immunoglobulin effectively destroys the fetal red blood cells before the mothers immune system is stimulated. The mother thus avoids becoming actively immunized against the Rh antigen and will not produce antibodies that could attack the red blood cells of a future Rh-positive fetus.

Human serum, the fluid portion of the blood that remains after clotting, contains various proteins that have been shown to be under genetic control. Study of genetic influences has flourished since the development of precise methods for separating and identifying serum proteins. These move at different rates under the impetus of an electrical field (electrophoresis), as do proteins from many other sources (e.g., muscle or nerve). Since the composition of a protein is specified by the structure of its corresponding gene, biochemical studies based on electrophoresis permit direct study of tissue substances that are only a metabolic step or two away from the genes themselves.

Electrophoretic studies have revealed that at least one-third of the human serum proteins occur in variant forms. Many of the serum proteins are polymorphic, occurring as two or more variants with a frequency of not less than 1 percent each in a population. Patterns of polymorphic serum protein variants have been used to determine whether twins are identical (as in assessing compatibility for organ transplants) or whether two individuals are related (as in resolving paternity suits). Whether the different forms have a selective advantage is not generally known.

Much attention in the genetics of substances in the blood has been centred on serum proteins called haptoglobins, transferrins (which transport iron), and gamma globulins (a number of which are known to immunize against infectious diseases). Haptoglobins appear to relate to two common alleles at a single chromosome locus; the mode of inheritance of the other two seems more complicated, about 18 kinds of transferrins having been described. Like blood-cell antigen genes, serum-protein genes are distributed worldwide in the human population in a way that permits their use in tracing the origin and migration of different groups of people.

Hundreds of variants of hemoglobin have been identified by electrophoresis, but relatively few are frequent enough to be called polymorphisms. Of the polymorphisms, the alleles for sickle-cell and thalassemia hemoglobins produce serious disease in homozygotes, whereas others (hemoglobins C, D, and E) do not. The sickle-cell polymorphism confers a selective advantage on the heterozygote living in a malarial environment; the thalassemia polymorphism provides a similar advantage.

Read more:

Human genetics | biology | Britannica.com

Travel – Wikipedia

Travel is the movement of people between distant geographical locations. Travel can be done by foot, bicycle, automobile, train, boat, bus, airplane, ship or other means, with or without luggage, and can be one way or round trip.[1][2] Travel can also include relatively short stays between successive movements.

The origin of the word “travel” is most likely lost to history. The term “travel” may originate from the Old French word travail, which means ‘work’.[3] According to the Merriam Webster dictionary, the first known use of the word travel was in the 14th century. It also states that the word comes from Middle English travailen, travelen (which means to torment, labor, strive, journey) and earlier from Old French travailler (which means to work strenuously, toil). In English we still occasionally use the words “travail”, which means struggle. According to Simon Winchester in his book The Best Travelers’ Tales (2004), the words “travel” and “travail” both share an even more ancient root: a Roman instrument of torture called the tripalium (in Latin it means “three stakes”, as in to impale). This link may reflect the extreme difficulty of travel in ancient times. Today, travel may or may not be much easier depending upon the destination you choose (e.g. Mt. Everest, the Amazon rainforest), how you plan to get there (tour bus, cruise ship, or oxcart), and whether you decide to “rough it” (see extreme tourism and adventure travel). “There’s a big difference between simply being a tourist and being a true world traveler”, notes travel writer Michael Kasum. This is, however, a contested distinction as academic work on the cultures and sociology of travel has noted.[4]

Reasons for traveling include recreation,[5] tourism[5] or vacationing,[5] research travel,[5] the gathering of information, visiting people, volunteer travel for charity, migration to begin life somewhere else, religious pilgrimages[5] and mission trips, business travel,[5] trade,[5] commuting, and other reasons, such as to obtain health care[5] or waging or fleeing war or for the enjoyment of traveling. Travellers may use human-powered transport such as walking or bicycling; or vehicles, such as public transport, automobiles, trains and airplanes.

Motives for travel include:

Travel dates back to antiquity where wealthy Greeks and Romans would travel for leisure to their summer homes and villas in cities such as Pompeii and Baiae.[7]While early travel tended to be slower, more dangerous, and more dominated by trade and migration, cultural and technological advances over many years have tended to mean that travel has become easier and more accessible.[8] Mankind has come a long way in transportation since Christopher Columbus sailed to the new world from Spain in 1492, an expedition which took over 10 weeks to arrive at the final destination; to the 21st century where aircraft allow travel from Spain to the United States overnight.

Travel in the Middle Ages offered hardships and challenges, however, it was important to the economy and to society. The wholesale sector depended (for example) on merchants dealing with/through caravans or sea-voyagers, end-user retailing often demanded the services of many itinerant peddlers wandering from village to hamlet, gyrovagues (Wandering Monks) and wandering friars brought theology and pastoral support to neglected areas, travelling minstrels practiced the never-ending tour, and armies ranged far and wide in various crusades and in sundry other wars.[7]Pilgrimages were common in both the European and Islamic world and involved streams of travellers both locally (Canterbury Tales-style) and internationally.[9]

In the late 16th century it became fashionable for young European aristocrats and wealthy upper class men to travel to significant European cities as part of their education in the arts and literature. This was known as the Grand Tour, it included cities such as London, Paris, Venice, Florence and Rome.However, The French revolution brought with it the end of the Grand Tour.[7]

Travel by water often provided more comfort and speed than land-travel, at least until the advent of a network of railways in the 19th century. Travel for the purpose of tourism is reported to have started around this time when people began to travel for fun as travel was no longer a hard and challenging task. This was capitalised on by people like Thomas Cook selling tourism packages where trains and hotels were booked together.[10] Airships and airplanes took over much of the role of long-distance surface travel in the 20th century, notably after the second World War where there was a surplus of both aircraft and pilots.[7]

Travel may be local, regional, national (domestic) or international. In some countries, non-local internal travel may require an internal passport, while international travel typically requires a passport and visa. A trip may also be part of a round-trip, which is a particular type of travel whereby a person moves from one location to another and returns.[11]

Authorities emphasize the importance of taking precautions to ensure travel safety.[12] When traveling abroad, the odds favor a safe and incident-free trip, however, travelers can be subject to difficulties, crime and violence.[13] Some safety considerations include being aware of one’s surroundings,[12] avoiding being the target of a crime,[12] leaving copies of one’s passport and itinerary information with trusted people,[12] obtaining medical insurance valid in the country being visited[12] and registering with one’s national embassy when arriving in a foreign country.[12] Many countries do not recognize drivers’ licenses from other countries; however most countries accept international driving permits.[14] Automobile insurance policies issued in one’s own country are often invalid in foreign countries, and it is often a requirement to obtain temporary auto insurance valid in the country being visited.[14] It is also advisable to become oriented with the driving-rules and -regulations of destination countries.[14] Wearing a seat belt is highly advisable for safety reasons; many countries have penalties for violating seatbelt laws.[14]

There are three main statistics which may be used to compare the safety of various forms of travel (based on a DETR survey in October 2000):[15]

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Travel – Wikipedia

World Tourism

If youre looking to travel this Labor Day weekend (and lets be honest, who isnt?), you may be in for a surprise when you hit airport security and baggage check lines. According to industry analysts, an expected 2 million passengers per day will fly between Wednesday September 2nd and Tuesday September 8th. If you traveled last year around the same time, experts say to expect even heavier traffic this year. Apparently, travel this year will see a 3% increase over the same time last year, which means about an extra 60,000 passengers per day using airline services. [Read more]

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World Tourism

South African Cuisine: Smiley (Fire-Roasted Goat Head) and …

Oct 5, 2012

Johanna Read /Africa Travel, Food Travel, Namibia, South Africa, Travel Abroad /

Leopard (not on the menu). Photo by Johanna Read

Smiley. A lovely word. A not so lovely dish.

Im in southern Africa. This is more of a seeing animals trip than an eating animals trip, but how can I resist the opportunity to eat something Ive never had before?

Many people have told me to keep an eye out for smiley. Cool Im a smiley person, I say. Whats smiley?Im thinking of foodsthat make me smile:dark chocolate and raspberries; lamb-sicles; gelato fromIl Crispinoin Rome; street food in Luang Prabang, Laos; passion fruit anything, twice-fried French fries with truffled ketchup ..

Then Im told smiley is the head of a sheep or a goat, brains and eyeballs included, that is cooked over a fire so that its lips pull back into a smile. Yum.

Hmmmm. Maybe Im not as much of a smiley person as I thought.

Biltong

Biltongis dried beef (sometimes oryx, kudu or ostrich), similar to beef jerky.Photo by Johanna Read

I meet up with LaurenCohen a new friend originallymet on Twitter to have dinner at one of the many fine restaurants in Cape TownsVictoria and Alfred Waterfront. The Waterfront is both a workingharborand a hub for eating, shopping and entertainment, for tourists and locals alike.Tonight we tryTasca De Belem, which serves authentic Portuguese and Turkish mains and tapas / meze. We sit outside with a view of the quay (with heat lamps and blankets available it is July, i.e. mid-winter,after all). I eat fabulous tuna, barely seared as ordered, with a delicious Portuguese prego sauce garlic, cumin and chili pepper goodness. I love that the sustainability and source of each fish aredescribed on the menu.

Of course the discussion is a lot about food, and about South Africanspecialties and Lauren mentions biltong. Bull tongue?! I ask, thinking of a variation of smiley. No. If youve ever had beef jerky, then youve eaten the very poor cousin of biltong. Biltong is dried beef (sometimes oryx, kudu or ostrich) and comes insausage form as well as thinly sliced. It is way moreflavorfuland much better-textured than beef jerky. Lauren treats us to both from theCity Grill Steakhouse, a couple doors down.

Having gorged myself at dinner, I save the biltong for the next dayspatkos Afrikaans for road food for my trip to the Cape of Good Hope.It is much appreciated after the 159 meter stair climb up to the lighthouse on an empty stomach.

Game

It is surprisingly not that hard to spend your days in Namibian animal reserves looking at game and spend your evenings eating it. No, I didnt eat leopard, cheetah, elephant or anything like that. But oryx, kudu and eland are all delicious. They are all beautiful too (and raisedsustainably).

What do they taste like? No not like chicken! But a lot like beef. The oryx is the most delicious like a dry-aged steak, both lean and juicy at the same time. Maybe a bit like lamb chops. Kudu is similar, but not asflavorfuland drier. And eland even more so.

Ill order oryx again if I ever see it on a menu, but will probably skip the kudu and eland. Theyre better lion food anyway.

Malva pudding from Tasca restaurant. Photo by Johanna Read

Malva pudding

Pudding nothing to be nervous about with dessert! Malva pudding a traditional South African dish, adopted from the Dutch is a pudding in the English sense of the word. It is a cake with sauce, served warm,resembling sticky toffee pudding.

Every Malva pudding I try (and there are several)is different. I preferthe warmer stickier ones to the cooler drier ones. The taste is somewhat like a caramel cake. I had to check recipes to see what givesit that uniqueflavor apricot jam of all things. Regardless of where you are in the world, you should be able to find the ingredients to make this one at home (see recipe below).

And the smiley?

Well, lucky for me I never did come across the smiley. After seeing photos I cant say Im too upset over it.

Maggies Malva Pudding (serves 6)

Michael Olivier, Cape Towns Wine and Food Guru, says that this is the benchmark malva pudding recipe. It is by Maggie Pepler and served at the Boschendal Restaurant. For more info see hissite.

Cake:1 cup flour1 tablespoon bicarbonate of soda (baking soda)1 cup sugar1 egg1 tablespoon apricot jam1 tablespoon vinegar1 talespoon melted butter1 cup milk

Sauce: cup cream cup milk1 cup sugar cup hot water cup butter

Preheat oven to 180C / 350F.With butter, grease an ovenproof dish approximately 30cm X 20cm X 5cm. Glass or ceramic best do not use an aluminium, enamel or metal container. Cut a piece of aluminium foil to cover the dish, and grease it well with butter on one side.

Sift the flour and the baking soda into a bowl and stir in the sugar.In another bowl beat the egg very well and add the remaining wet cake ingredients one by one, beating well between each addition.Using a wooden spoon beat the wet ingredients into the dry ingredients and mix well.

Pour the batter into the prepared dish, cover with the foil, greased side down, and bake 45 minutes until well risen and brown. Bake a further five minutes without the foil if not sufficiently brown. Be careful not to under-bake: if not sufficiently baked the dessert will not soak up all the sauce.When the pudding is almost done, heat the ingredients for the sauce, ensuring that you melt all the sugar and butter.When the pudding is done, remove from the oven, take off the foil and pour over the sauce.

Serve hot, warm or at room temperature, though the warmer the better. If desired, serve with some whipped cream or vanilla custard.

TravelEater, aka Johanna Read, is a Canadian who loves travelling and loves eating, but hates eating tourist food. She collects — and shares — advice about eating around the world (and about what to do between snacks). Johanna is World Travel Buzz’s new International Eating Expert and will be writing a monthly column.

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South African Cuisine: Smiley (Fire-Roasted Goat Head) and …

50 Awesome Travel Blog Name Ideas – This World Rocks

When I was getting ready to launch mytravel blog, I had a really tough time picking a name for the blog. In reality, the name of a travel blog isnt as important as you might think. It isnt as important as quality writing, a well-designed site, a good brand, and a lot of content. However, your name is still a big piece of the puzzle, and should be something you like and can live with. To come up with my blogs name, I did an exercise to come up with as many awesome travel blog names as possible and then slowly narrowed it down to my current name. I thought I would share this list with any future travel bloggers who are currently brainstorming for a name. Not all of these were from my original list, as I have added more since, so go ahead and use this list as a starting point for your own brainstorming.UPDATE: Feel free to use any of these names for your own travel blog. People have been emailing me a lot asking if they can use a name on the list. You dont need my permission to use any of these names since I dont own any of them. I also dont own any of the domain names, so if its already taken there isnt anything I can do. Good luck in your search!

1. Out of the Office For a former cubicle worker who wants to quit and to put up anindefiniteemail out of office notification.

2. Binge Travelers BingeTravelers.com is available too, which is a great domain.

3. Tweet Pray Love The digital version of famous book/movie. Thanks to @AndyMonfre for this one!

4.Losing Sight of the ShoreHow does the saying go? You cant discover a new ocean until you have the courage to lose sight of the shore.

5. Forks In The Road For a traveler who loves food and decisions!

6. Corners of the World This is a good domain name that is available: CornersoftheWorld.com

7. Navigatio No, I didnt forget the N, Navigatio is actually Latin forVoyage.

8. The Hum of the Earth Instead of looking for the scum of the Earth, you seek the good, or what makes us hum. Domain is available: HumoftheEarth.com

9. Tray Tables & Seat Backs Travel bloggers can recite this entire speech by memory.

10. Mice Will Play When the cats away

11. Uneven Pavement The types of roads travelers crave

12. Loose Gravel Same idea as above

13. Cats and Dogs Living Together Are you planning on having chaotic travels? Heres a salute toBill Murrays description of chaos in Ghostbusters.

14. Get Busy Livin ForShawshank fans. Instead of Livin you could replace it with your name, like Get Busy Jenny

15. Someday This Day Make your own meaning of it.

16. Showering in the Ocean For the beach lover.

17. Bathing in the Ocean Variation of above.

18. Both Paths For a traveler like us who likes mixing in both the beaten path and unbeaten path.

19. Where the Heart Is Home is

20. The Long and Winding One of my favorite Beatles songs.

21. Cark Muban Mark Cuban once did a gap year, so pay homage to him by creating his alter ego and doing your own trip.

22. All Systems Whoa There are a lot of names you can create by changing the word go to whoa in popular catch phrases.

23. Away We Whoa See above

24. Ready, Set, Whoa See above

25. On the Whoa Ok, you get the idea by now

26. Here Goes Here goes nothing!

27. One Point Five Billion Inches The circumference of the Earth is 1.5 billion inches.

28. Around the Tellus Tellus is Latin for Earth

29. Around the Orbis Orbis is Latin for World

30. Turn Turn Turn Referring to the constant turning while traveling, both good turns and bad.

31. YOUR NAME on Earth This works really well if your name rhymes with heaven, i.e. Kevin, Devin, Gavin, Evan, Melvin, etc

32. Cold Turkey This could be for a blogger who had to quit something addictive in order to travel. i.e. shopping, alcohol, drugs, video games, over-working, etc.

33. Like Nothing Ive Seen A blog about seeing and experiencing new, exotic adventures.

34. Salt of the Earth This sounds a bit Biblical, but thats because it is a Bible phrase. However, it can still apply the our natural world. Domain available: SaltoftheEarth.com

35. Off the Face Basically letting people know youve fallen(jumped) off the face of the Earth.

36. Reset ReBoot Record Someone who left home to get a fresh start, and is recording the progress in the blog. You could do a cool logo with the three Rs.

37. Re* Re* Record Replace the first two re-words with any two words on this list. Find two words that fit your situation the best.

38. One Big Rock Thats all Earth is right?

39. Off and Running For all the travel runners out there.

40. Travel Travel Travel Pizza Pizza

41. Text Me Later Im gone for a while.

42. My Final Frontier Star trek fan?

43. Each City a Rhapsody For the musically inclined.

44. Jet Set Brunette Sorry blondes, this one isnt for you.

45. Redefined Timeline Define the change of pace and scenery in your life.

46. Every Corner a Story Awesome stories are everywhere you look, all over the globe.

47. Miles and Smiles Away Miles, and miles, and miles, and miles, away.

48. Roam Sweet Roam Roam is the new Home (apparently there was a documentary with this title in 1996)

49. Why Dont You Babe A play on the Supremes song

50. No Particular Place to Go For the wandering blogger.

51. So This is How I Die From Stetson at Sergios Samba

52. WanderingOmies.com From Brandon at TheYogaNomads.com

These are from Brian at Blancette:

53.Three If By Sky modern twist on an old classic, nobody suspected the British of coming through the air.

54. Traveling Like LeBron Ah ah ahtoo many steps

55. Hostel Takeover no hostilities on this blog

56. Bloggers Without Borders give back to the world and do some pro bono blogging.

57. Boats and Phos: A Maritime Tour of Southeast Asia

58. The Gumshoes some of us never gave up chasing Carmen Sandiego

59. The Planeteers which one are you? Earth, wind, water, fire, or heart?

60. SergeantPlanet cause nobody out ranks the Captain

These are from Tina at GypsySpirit.com:

61. Nowhere in Particular

62. Gypsy Soul

63. Riding the Waves

64. Smells Like Gypsy

65. Gypsy Rhapsody

66. Gone Traveling

67. Life in a Bag

68. Hugging the Road

69. [yourname] Pilgrim

70. [yourname] Supertramp

These are from WildWanderess.com:

71.The Runaway Girl

72. Gypsy Girl Travels

73. The Simple Sojourn

74. Rooftops and Flipflops

75. Edge of the Sand

76. The Lost Gurl

77. Gutsy Girl Travel

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Total Lunar Eclipse on January 20-21

Watch as the Super Full Moon turns blood red in the sky above North and South America, Europe, and parts of Africa on the evening of Sunday, January 20 or early morning on Monday, January 21 depending on the time zone. Check your local times, eclipse maps, animations, and the weather. We will LIVE stream the eclipse. Full Story

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Understanding Memetics – SCP Foundation

Summary, for those in a hurry:

Memetics deals with information transfer, specifically cultural information in society. The basic idea is to conflate the exchange of information between people with genetic material, to track the mutation of ideas as they are transmitted from one person to the next in the way you could track viral transmissions and mutations. However, a meme also provides benefits to the carrier if they spread it.

Meme : Memetics :: Gene : Genetics

Memetics does NOT refer to telepathy, ESP or any imaginary psychic mental magic. These words are memetic, and if you understand them then they are having a completely ordinary memetic effect on you.

Memetics in regards to SCP objects tends to focus on the impossible rather than the mundane, regarding effects that are transmitted via information. In general, the effects themselves should remain in the realm of information. A memetic SCP would be more likely to be a phrase that makes you think you have wings as opposed to a phrase that makes you actually grow a pair of wings. If you write up magic words that make people grow wings, it should be described as something other than memetic.

Memetic SCPs do not emanate auras or project beams. They are SCPs which involve ideas and symbols which trigger a response in those who understand them.

Memetic is often incorrectly used by new personnel as the official sounding term for “Weird Mind Shit.” However, that is not actually what memetic means. These words are memetic. They are producing a memetic effect in your mind right now, without any magical mind rays lashing out of your computer monitor to grasp your fragile consciousness. Memes are information, more specifically, cultural information.

Outside of the Foundation’s walls the concept of memetics is not taken very seriously; it is a theory that conflates the transfer of cultural information with evolutionary biology.

meme : memetic :: gene : genetic

The idea was that certain memes prosper and others wither the same way certain genes produce stronger offspring that out-compete creatures with different genes. Also, it is easy to compare the spread and mutation of information to the spread of a virus. The reason we use the term memetic in our work is largely due to this, as the truly dangerous memes out there can spread like wildfire due to the fact that the very knowledge of them can count as an infection.

Understanding the true nature of memetic threats is critical to surviving them. You cannot wear a special set of magical goggles made of telekill to protect yourself from a meme. THE GOGGLES DO NOTHING. If you just read those words in your head with a bad Teutonic accent, congratulations on being victim to yet another memetic effect. If you did not know that phrase was an oft-repeated quote from the Simpsons then congratulations; you are now infected with that knowledge and are free to participate in its spread.

A meme perpetuates itself by being beneficial to the carrier to spread to new hosts. You now understand that THE GOGGLES DO NOTHING; you’re in on the joke. However, you might have friends who aren’t, and don’t get it. It benefits you to explain them, because then you both have something new to laugh together about when it gets brought up. This is what makes a meme effective – how much incentive a carrier has to spread it. Unless an anomalous meme’s effect is the compulsive urge for the carrier to infect others, there needs to be incentive to spread it.

An artifact can no more have a memetic aura or project a memetic beam than a creature could have a genetic aura or genetic beam. Even though you could imagine a creature with genes that allow it to produce some kind of aura or beam like a big doofy X-man, remember that the examples we have of such creatures in containment are not getting their super-powered emanations from anything resembling our scientific understanding of genetics and biology. Neither are the memetic artifacts. We contain these things specifically because we cannot understand or explain them yet. At the end of the day we’re still using a clumsy concept to describe things we don’t have a full grasp of.

It is very rare that anything with a dangerous memetic component could be described as hostile to begin with. We do not contain memetic threats because they are out to get us. They are threats because it is dangerous for us to merely perceive them. It is exceptionally rare for dangerous memes to even have anything resembling sapience with the exception of certain known entities which exist entirely within the medium of “cultural information” such as SCP-, SCP-732 and SCP-423.

A dangerous meme is basically a trigger that sets off something inside of you that you may or may have not been aware of. What would your knee jerk reaction be to knowing that your rival is sleeping with your one true love? How would you react if you were to unwittingly catch them in the act? That kind of sudden revelation can make a mild mannered citizen into a killer, so don’t be surprised that there are other strange bits of information out there that can break the human mind in different yet equally drastic ways.

Protecting yourself from memetic threat is very tricky and can be worse than the threat itself. There are reasons that we behave the way we do, there are reasons our emotions soar when we hear just the right combination of sounds in a piece of music. Do you want to stop thinking about the Simpsons or your obnoxious nerdy friends that quote it every time you hear the phrase THE GOGGLES DO NOTHING? That would require forgetting about the Simpsons and your friends.

Do you want to survive hearing or reading the phrase ” ?” Well, sadly we don’t quite know what other information you need to forget or know to prevent [DATA EXPUNGED] but we’re getting better. Lobotomies and pills help, and are one of the few times that the cure is not worse than the disease. The sum total of our human condition; our cultural knowledge and upbringing and memories and identity; this is what makes us susceptible to the occasional memetic compulsion.

So it’s not the basalt monolith or its bizarre carvings that is making you strangle your companions with your own intestines, the problem was within you all along.

Should you ever find yourself under a memetic compulsion and aware of the fact, remember that there are certain mental exercises that you can perform which may save your life or the lives of your companions. Changing the information your mind is being presented with may just change how you react to it, and the more abrupt or absurd the change is the better.

Imagine the fearsome entity is wearing a bright pink nightgown. Draw a mustache on the haunted painting. Pee on the stone altar. Wear the terrible sculpture like a hat.

And if all else fails, bend over and kiss your ass goodbye. I’m not kidding. That could actually help.

– Dr. Johannes Sorts received a special dispensation to use the word “doofy” in this document

But seriously

This was originally intended as a piece of fiction on its own before it got stuck into the information bar with plenty of other plainly out-of-character writing guides. So here’s the important things to take away:

1 – “Memetics” is a specific concept regarding information exchange. It has nothing to do with telepathy or ESP or psychic compulsions.

2 – SCP-148 has no effect on anything memetic. Don’t screw this up or we will give you an incredibly hard time about it.

3 – Psychic compulsions are lame and you should think twice before using them in your new SCP, even if you avoid misusing the term “memetic” when you do it.

4 – Sorts’ Rule for all memetic SCPs is “Memetic effect + crazy to death = failure.”

5 – Wear it like a haaaaat!!

Read the rest here:

Understanding Memetics – SCP Foundation

Memetics | Definition of Memetics by Merriam-Webster

: the study of memes Memetics sees ideas as a kind of virus, sometimes propagating in spite of truth and logic. Its maxim is: Beliefs that survive aren’t necessarily true, rules that survive aren’t necessarily fair and rituals that survive aren’t necessarily necessary. Things that survive do so because they are good at surviving. Los Angeles Times, 20 Mar. 1999

Read more:

Memetics | Definition of Memetics by Merriam-Webster


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