Fast radio bursts are one of astronomys tantalizing unsolved mysteries. These sudden pulses of radio waves come from far outside our galaxy. They last about a millisecond. And sometimes, the signals repeat.

Until recently, thats about all scientists could tell you about fast radio bursts, or FRBs. Our radio telescopes, which pick up noise rather than light, first detected them in 2007; since then, weve recorded a few dozen more, but not enough to be able to put together a compelling theory of what causes them.

With the origin of these signals still unknown, some scientists notably the chair of the Harvard astronomy department, Avi Loeb speculate aliens could be sending them.

Now, researchers based in Canada, where a radio telescope exceptionally well equipped to detect FRBs began operating in 2018, have added a new piece to the puzzle. A few previously detected FRBs had been shown to repeat sporadically, without any regular pattern. But by observing the sky from September 2018 through October 2019, the researchers in Canada found 28 bursts including one that repeats with a very regular pattern indeed: It appears every 16.35 days, to be exact.

This is the first time scientists have detected such a pattern in an FRB source. The peculiar signal is coming from a massive spiral galaxy 500 million light-years away. The source sends out one or two bursts of radio waves every hour, over four days. Then it goes quiet for 12 days. Then the whole process repeats.

So why is a radio signal repeating every 16 days like clockwork, and what can that teach us about its origins?

Thats the central question of a new paper authored by the Canadian Hydrogen Intensity Mapping Experiment in collaboration with the Fast Radio Burst Project (CHIME/FRB).

There are a couple of things we know for sure. The 16-day periodicity cannot be occurring by chance coincidence, the scientists write, and its an important clue to the nature of the object. Its clear that the FRB cant be originating from a cataclysmic event, like a star going supernova, since thats a one-time affair.

But beyond that, the scientists really arent sure. They propose a few possibilities.

One explanation is orbital motion. Celestial bodies are known to orbit on regular timescales, so a pair of objects like a star and a black hole could account for the 16-day pattern. Given the sources location in the outskirts of a massive spiral galaxy, the paper says, a supermassive black hole companion seems unlikely, although lower-mass black holes are viable.

The authors say FRBs could be generated if giant radio pulses from an energetic neutron star are eclipsed by a companion object. They also note that periodicity could arise from the rotation of a star, but thats a tricky hypothesis: Previously observed sources have had way shorter periodicities (a few hours, not a couple of weeks) and way less strength (were talking nine orders of magnitude less) than FRBs have.

In short, the authors dont know whats causing FRBs. But aliens are not on their list of possibilities. They end their paper calling for more research.

While grounded speculation among astrophysicists suggests that FRBs are caused by neutron stars, stars merging, or black holes, its a different theory that has caught hold of the public imagination: Maybe theyre caused by intelligent alien life.

A study by Avi Loeb and Manasvi Lingam of Harvard University, published in 2017, argued that the patterns could plausibly result from extraterrestrials transmitters. The paper is theoretical; it doesnt propose any evidence for the aliens hypothesis, it just argues that itd be compatible with the recorded data so far. They concluded itd be physically possible to build such a transmitter if you had a solar-powered, water-cooled device twice the size of Earth.

The hypothesis raises some obvious questions. FRBs come from all over space, not just from one particular region. Are we to assume that these aliens are sophisticated enough to have spread across many galaxies, but that there are no signs of them other than these energy bursts? Or that many civilizations independently settled on the same odd style of energy burst?

The 2017 paper argues for the latter possibility: that many civilizations have separately built such massive transmitters and are sending out FRBs. The latest estimates suggest that there are 10^4 [10,000] FRBs per day, the paper observes, which would suggest an implausible number of extremely busy, scattered alien civilizations. To resolve that, the paper argues that perhaps not all FRBs have an artificial origin only a fraction of them could correspond to alien activity.

But once we concede that FRBs can occur naturally, and conclude that at least some of them are occurring naturally, why conclude that any of them are artificial?

And if a civilization had the astounding technical capacities to build solar-powered, planet-size transmitters, wouldnt it be doing other things we could detect that would be less ambiguous?

The possibility that FRBs are produced by extragalactic civilizations is more speculative than an astrophysical origin, the paper concedes.

Indeed, thats what the CHIME/FRB researchers behind the new paper think. We conclude that the periodicity [of the FRB] is significant and astrophysical in origin.

Scientists disagree about how to interpret phenomena like FRBs in large part because they disagree about how plausible alien life is in the first place. In statistical terms, they have different priors, meaning that the background assumptions they are using to interpret the new evidence are different.

From one perspective, the universe is astonishingly large, full of habitable planets like Earth where life could evolve as it did here. Sometimes, that life would become intelligent. Wed expect such a universe to have lots of flourishing civilizations as well as lots of extinct ones.

This is clearly the expectation that motivates Harvards Loeb. As soon as we leave the solar system, I believe we will see a great deal of traffic out there, he said in a 2019 interview with Haaretz. Possibly well get a message that says, Welcome to the interstellar club. Or well discover multiple dead civilizations that is, well find their remains.

If you think that space is teeming with aliens, its not so much of a stretch to interpret astronomical phenomena as remnants of those aliens.

But if youre looking at the same data with the expectation that were alone in the universe, youre much likelier to conclude that theres a natural explanation for FRBs.

Its weird, given that the universe is so vast, that we seem to be alone in it. Physicist Enrico Fermi was the first to spell out this dilemma, and its named after him: the Fermi paradox. The paradox is that, under some reasonable assumptions about how often life originates and reaches technological sophistication, we should be able to detect signs of thousands or millions of other civilizations. And yet we havent. Recent investigations suggest that the paradox may have a mundane resolution under more accurate assumptions about how life originates, we are very plausibly, alone.

The disagreement between researchers who think advanced civilizations must be extremely rare and those who think theyre common is a fairly substantive one. For one thing, if advanced civilizations are common, then why cant we see them? We might be forced to conclude that theyre fairly short-lived. Thats Loebs take: The technological window of opportunity might be very small, he told Haaretz.

That take would have some consequences for us. If theres some danger ahead that destroys every technological civilization that runs into it, we might expect that were living in a vulnerable world where future technological advances will destroy us, too.

In that way, disagreements over aliens have big implications. But thats probably not the reason everyone cares about them. Offhand speculation about aliens tends to get vastly more coverage than anything else in astronomy. Whether were alone in the universe feels like a profoundly important question, for its implications for human civilization but also for its own sake. The lack of evidence suggesting phenomena like FRBs are alien in origin wont be enough to stop people from wondering.

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What is a fast radio burst? What causes the signal from space? - Vox.com

Since the 1960s, there has been a general consensus among astronomers and cosmologists that the majority of the Universe is made up of an invisible, mysterious mass (known as Dark Matter). While scientists still havent identified the candidate particle that makes up this mass, indirect tests and simulations have shown that Dark Matter must exist in order for the Universe to be the way it is.

In a fascinating twist, a team of European researchers conducted a simulation that looked at a Universe without Dark Matter. Using an alternative theory known as MOdified Newtonian Dynamics (MOND), the team created a computer simulation in which the galaxies were actually very similar to what we see in the Universe today. These findings could help to resolve one of the most enduring mysteries of modern cosmology.

The study that describes their findings (recently published in the Astrophysical Journal) was conducted by the Stellar Populations and Dynamics Research Group (SPODYR) led by Prof. Pavel Kroupa of the Helmholtz Institue for Radiation and Nuclear Physics at the University of Bonn. He was joined by Nils Wittenburg, a doctoral member of SPODYR, and Benoit Famaey the Research Director at the University of Strasbourg.

This theory that gravity behaves differently than previously thought (depending on the scale) was first proposed by Israeli physicist Prof. Dr. Mordehai Milgrom hence the alternative name Milgromian gravity. According to this theory, the attraction between two masses obeys Newtons Laws of Motion (aka. Universal Gravitation) only up to a certain point.

At lower accelerations, as is the case with galaxies, the influence of gravity becomes considerably stronger. In short, the attraction of a body depends not only on its own mass but also on whether other objects are in its vicinity. This theory is a possible explanation for why galaxies do not break apart as a result of their rotational speed.

MOND is also attractive because it makes the existence of Dark Matter (which remains unconfirmed) entirely superfluous. Nevertheless, MOND remains a largely unproven and untested theory, which is what Wittenberg and his colleagues sought to address. With the help of Famaey, the team employed computational software that conducts gravitational computations (which they designed) to simulate a cosmos where MOND exists.

This consisted of simulating the birth of the first stars and galaxies which are believed to have formed between 100,000 and 300,000 years after the Big Bang and how they have evolved since. What they found, interestingly enough, was that the distribution and velocity of the stars in the computer-generated galaxies followed the same pattern as those that are visible in the Universe today.

As Wittenburg, who was the lead author on the study, explained:

In many aspects, our results are remarkably close to what we actually observe with telescopes. Furthermore, our simulation resulted mostly in the formation of rotating disk galaxies like the Milky Way and almost all other large galaxies we know. Dark matter simulations, on the other hand, predominantly create galaxies without distinct matter disks a discrepancy to the observations that is difficult to explain.

In addition, the MOND simulation was virtually immune to changes in parameters, like the frequency of supernovae and their effect on the distribution of matter in galaxies. In the case of simulations where the existence of Dark Matter is assumed, however, changes in these parameters have a considerable effect. This is not to say that the MOND simulations were correct on all points.

For example, the simulations relied on some rather simple assumptions about the distribution of matter and the conditions present during the early Universe. Our simulation is only a first step, Prof. Kroupa emphasized. We now have to repeat the calculations and include more complex influencing factors. Then we will see if the MOND theory actually explains reality.

Invariably, when it comes to the dynamics and behavior of the Universe on the grandest of scales and longest of time periods, the jury is still out. While the existence of Dark Matter remains unproven, it is the only cosmological theory that is consistent with General Relativity an endlessly proven theory and the only working hypothesis for how gravity behaves on cosmological scales.

And while MOND provides some resolution to theoretical problems presented by Dark Matter, it presents problems of its own. In the near future, a number of next-generation observatories that could help resolve this mystery will be going into space including the James Webb Space Telescope (JWST) and the ESAs Euclid mission.

These and other missions will offer a better picture of the geometry of the Universe and improved measurements of the cosmic expansion. From this, scientists hope to gain a better understanding of how Dark Matter could have affected cosmic evolution not to mention Dark Energy, another cosmological mystery that is also the subject of debate!

Further Reading: University of Bonn, arXiv

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Astronomers Simulated How the Universe Would Look Without Dark Matter - Universe Today

Roundup Cygnus flies, SpaceX stands down, Rocket Lab is going to the Moon and New Horizons drops a massive dump (of new data) in this week's roundup. A heck of a way to celebrate the 30th anniversary of a view of Earth from really, really far away.

Northrop Grumman overcame both a delay and some unexpected bonus commentary (in the form of a Verizon interruption) to launch its latest freighter, Cygnus NG-13, to the International Space Station (ISS). The spacecraft, loaded with science and supplies, should turn up at the orbiting outpost at around 0905 UTC on Tuesday.

NASA astronaut Andrew Morgan will use the ISS's robotic arm to capture the Cygnus and install it on the Earth-facing port of the Unity module while fellow 'naut Jessica Meir keeps an eye on things. The spacecraft is scheduled to remain docked to the ISS until May.

The launch marks the 13th successful mission of the freighter. Memorably, the third operational flight ended in a fireball just after launch in 2014 following a catastrophic failure involving the elderly Russian engines of the 130-variant Antares rocket. Excepting a brief flirtation with the Atlas, the Cygnus has continued to fly on the Antares, although using somewhat more recent RD-181 power plant.

The next batch of 60 Starlink satellites remained rooted to a Cape Canaveral pad this weekend as engineers opted to take a look at a potentially iffy valve on the second stage of the launcher.

Our suspicion that an astronomer snuck up in the dead of night and had at the thing with a hammer is, of course, totally unfounded. After all, Elon has said that the albedo issue is going to get better. No, really, it will. Elon said so:

The launch, now scheduled for 17 February, will be the fourth flight for the first stage of the Falcon 9. The stage has lofted two Dragon freighters bound for the ISS, CRS-17 and CRS-18, and, most recently, the JCSAT-18/Kacific1 mission in December 2019. The company plans to recover the first stage once again as well as having another crack at catching the fairing halves.

In a now deleted tweet, NASA's commercial crew tentacle heralded the arrival in Florida of the next Crew Dragon capsule, which will be used for the upcoming Demo-2 mission. Astronauts Bob Behnken and Doug Hurley will clamber into the spacecraft for a trip to the ISS in the coming months.

NASA proudly declared that the SpaceX capsule would be the first to launch a crew from American soil since the shuttles were rolled off to museums.

The tweet was accompanied by a blog post giving SpaceX a nod. The original post was rapidly updated since while Boeing's capsule may have managed just one, near-disastrous flight and SpaceX's spacecraft has survived an exploding Falcon 9 as well as paying an uncrewed visit to the ISS it's still a two-horse race.

The internet, alas for NASA, never forgets.

The tweet was hastily replaced by one that doubtless made faces at Boeing, manufacturers of the Calamity Capsule Starliner CST-100, less frowny.

We imagine that Virgin Galactic, which has already sent Americans into space (depending on which definition you're using), might have had a thing or two to say about that assertion too, though the suborbital lobs in Branson's much delayed glider are quite a bit different to SpaceX and Boeing's orbital ambitions.

While it is over a year since NASA's New Horizons probe made its flypast of the Kuiper Belt Object Arrokoth (formerly known as 2014 MU69), the spacecraft has continued to return to Earth the data it captured during the event. Last week, the team reported more findings, giving new insights into how planetesimals (the building blocks of planets) are formed.

Arrokoth consists of two lobes, and the gang has pieced together a picture of how the object came to be; two objects formed close together and orbited each other at low velocity before gently merging to create the 22-mile long object.

The indications are that Arrokoth formed during the gravity-driven collapse of a cloud of solid particles rather than through hierarchical accretion (the slamming together of planetesimals to form larger bodies).

The probe, now 7.1 billion kilometres from Earth and heading deeper into the Kuiper Belt at nearly 50,400 kilometres per hour, has more observations to transmit, and Principal Investigator for the mission Alan Stern told The Register that it would be 2021 before everything was down.

This summer the team will start searching for more bonus KBOs for the probe to visit, should fuel allow.

Having made much of its lunar ambitions last year, Rocket Lab was cock-a-hoop over its selection by NASA last week for the upcoming Cislunar Autonomous Positioning System Technology Operations and Navigation Experiment (CAPSTONE) mission, which will be launched from the company's Launch Complex 2 at the Wallops Flight Facility in Virginia, USA. The CAPSTONE satellite will be sent on its way by Rocket Lab's Photon platform, eventually operating in a near-rectilinear halo orbit around the Moon.

CAPSTONE will pass as close as 1,000 miles and as far as 43,500 miles from the lunar surface.

The mission is slated for launch in early 2021, and it will take nearly three months for CAPSTONE to enter its target orbit ahead of spending six months demonstrating operations in the region where NASA hopes to send the Lunar Gateway. Should the latter, of course, survive the determination of lawmakers to sacrifice sustainability on the altar of getting flags on footprints on the regolith by 2024.

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SpaceX's next Starlink volley remains stuck on Earth to glee of astronomers everywhere - The Register

Near Earth objects. Credit: ESA P.Carril.

Three Leiden astronomers have shown that some asteroids that are considered harmless for now, can collide with Earth in the future. They did their research with the help of an artificial neural network. The results have been accepted for publication in the journal Astronomy & Astrophysics.

Using a supercomputer, the researchers integrated the orbits of the sun and its planets forward in time for 10,000 years. After that, they traced the orbits back in time while launching asteroids from the Earths surface. During the backwards calculation, they included the asteroids in the simulations in order to study their orbital distributions at todays date. In this way, they acquired a database of hypothetical asteroids for which the researchers knew that they would land on the Earths surface.

Astronomer and simulation expert Simon Portegies Zwart explains: If you rewind the clock, you will see the well-known asteroids land again on Earth. This way, you can make a library of the orbits of asteroids that landed on Earth. The library of asteroids then served as training material for the neural network.

The first set of calculations was performed on the new Leiden super computer ALICE, but the neural network runs on a simple laptop. The researchers call their method Hazardous Object Identifier (HOI), which means hi or hello in Dutch.

The neural network can recognize well-known near-Earth objects. In addition, HOI also identifies a number of hazardous objects that were not previously classified as such. For example, HOI discovered eleven asteroids that, between the years 2131 and 2923, come closer than ten times the Earth-Moon distance and are larger than a hundred meters in diameter.

That these asteroids have not previously been identified as potentially dangerous is because the orbit of these asteroids is so chaotic. As a result, they are not noticed by the current software from space organizations, which is based on probability calculations that use expensive brute force simulations.

According to Portegies Zwart, the research is only a first exercise: We now know that our method works, but we would certainly like to delve deeper in the research with a better neural network and with more input. The tricky part is that small disruptions in the orbit calculations can lead to major changes in the conclusions.

The researchers hope that in the future an artificial neural network can be used to detect potentially hazardous objects. Such a method is much faster than the traditional methods that space organizations use nowadays. By noticing asteroid on a collision course earlier, the researchers say, organizations can sooner think of a strategy to prevent impact.

Reference: Identifying Earth-impacting asteroids using an artificial neural network by John D. Hefele, Francesco Bortolussi and Simon Portegies Zwart, 4 February 2020, Astronomy & Astrophysics.DOI: 10.1051/0004-6361/201935983

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Astronomers Discover Eleven Dangerous Asteroids That Could Impact the Earth - SciTechDaily

In an effort to better understand the loss of the night sky due to light pollution, astronomers are calling on star-lovers and romantics to enjoy a night under the stars and give them a helping hand.

Each year, a group of astronomers, headed by Connie Walker at the National Science Foundation's National Optical-Infrared Astronomy Research Laboratoryin Tucson, Az., conduct the Globe at Night project, whichasks people around the world to step out and record how many stars they see in a specific constellation.

This, in turn, will allow them to gauge how dark or bright the night sky is in a particular location.

This year, the campaign has two runs, the first from Feb. 14 to 23 and the second from March 14 to 24.

"The Globe at Night is a social science program. That means every citizen can be an actual scientist and contribute data. And it's extremely easy to do," said Walker. "People can get involved very simply by just going out in the night, then looking up at the stars."

For Valentine's Day, the particular constellation the project is asking citizen scientists to look at is Orion.

Walker said that the whole process is easy, particularly as Orion is one of the most recognizable constellations in the northern hemisphere this time of year.

Participants are asked to visit the Globe at Night's webapp. It asks the time and date and your location (it can also do this automatically). Then there are seven illustrations to choose from, based on how many stars you saw. And finally, it asks you what the sky conditions were at the time of observation, i.e. partly cloudy, etc.

Walker explained the difference between the charts, which measure the magnitudes or apparent brightness of the star.

"So, one, it's like you would see in New York City, where there's just a couple of stars at best if you see any at all towards Orion," she said. "And thenseven, it's like you're in the national parks, where you see a couple thousand stars."

Most people probably don't think of light as a form of pollution, but it's something that has serious consequences for human health, the environment and wildlife.

For example, light pollution which is simply defined as the "inappropriate or excessive use of light," according to the International Dark-Sky Association (IDA) has affected the nesting habits of sea turtles. There are also estimates that 300,000 to one billion birds die annually from flying into buildings, because they are drawn to the bright lights at night.

As for humans, some studies have linked artificial light with forms of cancer.

About 54 per cent of people around the world live in cities. In Canada, that number soars to more than 80 per cent. As a consequence,most people across the planet have not seen the Milky Way.

Though many people and communities have switched to energy-saving LED lights, a 2017 study by Canadian Christopher Kyba, a light pollution researcher at the GFZ German Research Centre for Geosciences, found that these lights might actually be doing more harm than good.

Because the lights cost less, it appears more of them are being used. Kyba, who is involved in the Globe at Night project,is looking to conduct follow-up studies to determine if the night sky brightness is increasing or decreasing.

But why does it matter if we see the stars or not?

"It's part of our cultural heritage. It has inspired humanity, since the beginning of humanity, for tens of thousands of years. It is an infinite resource for wonder, and it's where all of our thoughts about science began," Walker said. "And it's not just science. It's the inspiration to be creative in terms of music, like [Gustav] Holst's The Planets,or literature like Shakespeare .... and then paintings, likeVan Gogh.

"If we take away that source of inspiration. What is it going to do to our culture?"

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Astronomers want you to help them count the stars this Valentine's Day - CBC.ca

Stargazing scientists have recently begun to focus on the prospect of encountering intelligent extraterrestrials, and the more they think about it the more they realize the first meeting probably wont be with little green men in flying saucers.

What aliens might look like is a growing question among astrobiologists, who are increasingly conjuring up creatures more Lilliputian than mega-brained or reptilian.

The intriguing possibility is they are, in fact, here, but we just dont know it, said Andrew Fraknoi, the emeritus chairman of the astronomy department at Foothill College who recently taught a course on aliens at the University of San Franciscos Fromm Institute and believes space aliens could very well be microscopic or unrecognizable as a life-form.

Fraknoi is on the board of the Search for Extraterrestrial Intelligence, known as the SETI Institute, based in Mountain View, where questions about alien civilizations are often discussed. He has long speculated that members of a civilization billions of years old might by now have evolved into a mechanical-biological mix, like a robot with a brain, capable of living for thousands of years as they travel through space.

But it is also possible, he said, that advanced civilizations would have sent into space thousands of tiny canisters holding the germs of life programmed to incubate and grow when they encounter suitable conditions around a star.

In all the mathematical models, a species that started early in the history of the galaxy and had the will and resources to diffuse could by now have filled many parts of the galaxy with its artifacts or biological spores, Fraknoi said.

The otherworldly speculation comes after the recent discovery of two interstellar objects zipping past Earth prompted a surge of interest among scientists in space travel and alien civilizations.

A spinning, red, cigar-shaped object called 1I/Oumuamua was spotted in 2017, followed by the sighting last year of a comet named 2I/Borisov. They were the first verified sightings in human history of objects speeding by from outside our solar system.

The objects, by their very existence, brought home to many astronomers the reality that rocks or vessels potentially carrying biological spores from other solar systems could actually reach Earth.

The notion got a major boost from Avi Loeb, the chair of Harvard Universitys astronomy department. He co-wrote a scientific paper suggesting that Oumuamuas odd, elongated shape and peculiar nongravitational acceleration could mean it is a mechanical probe a light sail driven by sunshine sent by an alien civilization.

The object, first spotted by the University of Hawaiis Institute for Astronomy, was, by all accounts, strange. Observations from Earth as it shot past the sun on Sept. 9, 2017, at a speed of 196,000 mph showed that it was slowly spinning, like a bottle on its side, and that it was missing the tail of gas or dust that would signify a comet.

Astronomers around the world immediately attacked Loebs hypothesis, and a subsequent study published in Nature Astronomy last year concluded that Oumuamua was a rocky conglomeration, not a space ship.

But Loeb said his point was that objects like Oumuamua and Borisov could have been synthetic and that humans would be well served by developing techniques for determining if such visitors were constructed. He believes the possibility of extraterrestrial life is too important for humans to discount without investigation, especially considering how useful it would be in figuring out the origin of life.

Intelligent life is more recent in the Earths history, but at the same time, given that it happened here, there is the possibility that it exists elsewhere, Loeb said. I dont think we should pretend that we are the only ones the smartest kid on the block because very likely we arent the smartest kid on the block.

The questions about what form alien beings might take are rooted in what is known as the Fermi paradox, named after Italian American physicist Enrico Fermi, who created the first nuclear reactor. He asked during a casual lunchtime conversation in 1950 why aliens have never been spotted, given the high probability of their existence.

SETI has been searching the skies for radio signals or some other sign of life beyond Earth for nearly four decades without a single peep.

Despite the failure, belief in the existence of extraterrestrial civilizations has only increased since Fermis time. Thats largely because powerful telescopes have recently detected numerous planets orbiting their stars at a habitable distance, known as the Goldilocks zone. Calculations indicate there are habitable planets around at least a quarter of the tens of billions of stars in the Milky Way Galaxy, possibly including the closest star, Proxima Centauri, 4.2 light-years from Earth.

Most astrophysicists believe life must have sprung up somewhere, some time, in the 13.5 billion years since the galaxy was formed. Given that our sun is 4.6 billion years old, Fraknoi said civilizations in other parts of the galaxy could have been using robotics, artificial intelligence and tapping the energy from their stars as many as 8 billion years before our solar system was created.

In other words, Fraknoi said, there has been ample time for a civilization to become advanced enough to send alien microbes or micro-artifacts around the galaxy, including to our solar system.

Astronomers have even concocted a sciency name, directed panspermia, to describe the act by an alien civilization of planting the seeds of life in another world.

Samantha Rolfe, a lecturer in astrobiology at Bayfordbury Observatory at the University of Hertfordshire in England, suggested recently that such organisms could be hidden inside what she called a microscopic shadow biosphere that is so different from ours that we dont even recognize it as biological in origin.

So why havent we found it? We have limited ways of studying the microscopic world as only a small percentage of microbes can be cultured in a lab, she wrote in an article for the Conversation website. We do now have the ability to sequence the DNA of unculturable strains of microbes, but this can only detect life as we know it that contain DNA.

Some have suggested that these alien life-forms could be small inactive spores floating in our solar system waiting for the right conditions to grow or as active monitors transmitters used by alien civilizations to determine whether Earthlings are a threat and might need to be eliminated.

Then again, a growing number of astronomers speculate that humanity itself might have originated somewhere else, possibly clinging to a chunk of rock ejected from a planet that was hit by a giant meteor.

We know there are rocks on Earth that came from Mars, so you could imagine that microbes could have potentially survived the journey, Loeb said. So its possible we are all Martians. If you can do it from Mars, you can potentially bring life from other planets in other galaxies.

Loeb recently published a paper calculating how asteroids could graze Earths atmosphere, scoop up microbes like the foamy cream off a latte, and potentially carry the seeds of life into outer space. Maybe, he and others suggest, this swapping of biological spores has happened since the beginning of time.

Either way, most experts believe an alien encounter is likely someday. The question, say those who think about such things, is whether humans will know it when they see it.

Potentially, we could be part of an experiment where life was planted on Earth and someone is watching, Loeb said. If thats the case, for sure they are disappointed. That would be my assessment by reading the morning newspaper.

Peter Fimrite is a San Francisco Chronicle staff writer. Email: pfimrite@sfchronicle.com Twitter: @pfimrite

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Scientists theorize that space aliens may already be here, but we dont recognize them - San Francisco Chronicle

Later Jaina mathematicians, Dharamanandana and Sundarasuri, continued explorations on magic squares and similar arrangements.

But from the fourteenth century, Kerala became the locus of several new siddhaantas, bhaashyas, karanas etc., that it is now called the Kerala school of mathematics.

The Kerala school

Shortly after Aryabhata, a mathematician called Haridatta had composed a work title Parahita Ganita based on Aryabhatiyam. After that we seem to have a vacuum in Kerala until Madhava (c 1340 AD) of Sangamagrama (Kudalur in Malayalam). What followed is an astonishing continuity of the guru-shishya parampara from Govinda Bhattatiri to Rajaraja Varma.

Madhava was famous as a skilled instrument maker. Indian historians of mathematics consider him the pitamaha of the Kerala school. Perhaps, his most famous contribution is sums of infinite series.

To calculate the circumference (paridhi) of a circle, said Madhava, we must multiply the diameter (vyaasa) by four times one minus tri-sharaa-aadi-vishama-samkhyaa-bhaktam-rNam. A phrase of compactness, which Aryabhata would have enjoyed. In other words, a sequence of odd (vishama samkhyaa) denominators (bhaktam) starting (aadi) with three (tri) and five (sharaa). The word sharaa here is a bhutasamkhya (see third essay) word for the five arrows of Manmatha, whose archery takes precedence over Rama and Arjuna and even Tripurantaka, in this case.

The sum of the series in the brackets adds up to /4, and is famous as the Gregory Leibniz series.

Madhavas series was quoted and a proof (upapatti) also given a century later by Jyeshtadeva.

Parameshvara Like Brahmagupta providing a sphuTam to Paitamaha Siddhaanta, Parameshvara observed that over time, predictions of earlier astronomers did not agree with observed positions based on calculations. In such a situation, he observed, one must adjust ones methods and calculations, because planets and stars will conform to them.

He titled his book Drg Ganitam. This title, which means Observed Calculations, is a popular phrase for jyotisham in south India, though the author himself has faded from public memory. His shishya NilakanTha referred to him as Paschimaam Bodhi, the western scholar.

Nilakantha Somayaaji More unknown than even Brahmagupta, was a polymath like Varahamihira. He was a scholar of Shad darshana (the six philosophies of Hinduism, and also in vyaakarana, chandas, the Bhagavata and various such literature. He also studied Vedanga Jyotisha, Pancha Siddhaantika, Brhat Samhita etc.

This historical curiosity and scholarship may have shined in other scholars, too, but in Nilakantha, we have contemporary evidence. He was also a prolific composer, of several texts.

He was a friend a Sundararaja, a jyotisha of the neighboring Tamil Nadu, and took the effort to compile a written list of answers for questions posed by the former, compiled into a book called Sundararaja Prashnottara.

Aficionados of European science may be reminded of the extensive correspondence of Franklin, Newton, Darwin, Humboldt etc.

A ninth century mathematician called Virasena in his commentary Dhavala gave this equation, that the sum of all powers of 1/4 is 1/3. One sees the reflection of this in Madhavas several infinite series. Nilakantha questioned this apparent absurdity. How does the sum of this infinite series increase to that finite value (1/3), and that it reaches finite value?

He reasoned and explained it by deriving the following sequence of results

As we add more terms, argued Nilakantha, the difference between 1/3 and the powers of 1/4 become extremely small, but never zero, unless we add terms up to infinity. In the 20th century, Ramanujan revelled in such series.

Quasi Heliocentric theory NilakanThas questioning of an assumption of planets latitudes (vikshepa), and his subsequent discovery was truly astronomical (pardon the pun). From the siddhantas through Bhaskaracharya, all astronomers used a slightly different method to calculate the latitudes of Mercury (Budha) and Venus (Shukra), than they did for the other planets. This niggled most of them, as inappropriate, especially Bhaskara, who then consoled himself with Prthudaka Svamis explanation.

But NilakanTha questioned this acceptance, and modified his computation, and effectively the orbital model for these planets. He came to the conclusion that these two planets revolve around the Sun (but in his model, the Sun still revolves around the Earth).

The geometrical argument is too complicated not only for this article, but even, perhaps, for those who are not astronomers, so I will only present a visual illustration of his model here.

The rest is here:

Indian Astronomy And Mathematics: When Kerala Became The Locus Of Genius - Swarajya

Using data from the Atacama Large Millimeter/submillimeter Array (ALMA), a team of Japanese researchers has found that Galactic cosmic rays affect the chemical reactions involved in the formation of nitrogen-bearing organic molecules in the atmosphere of Titan, the largest moon of Saturn.

This view of Titan is among the last images NASAs Cassini spacecraft sent to Earth before it plunged into the giant planets atmosphere. Image credit: NASA / JPL-Caltech / Space Science Institute.

Titan is a carbon-rich, oxygen-poor world with a wide range of organic and inorganic compounds, atmospheric energy sources, and liquid hydrocarbon seas and lakes.

This moon is the only planetary body in the Solar System, except Earth, where rainfall and seasonally flowing liquids erode the landscape.

In addition to a hazy mixture of nitrogen and hydrocarbons like methane and ethane, the atmosphere of this strangely Earth-like world also contains an array of more complex organic molecules.

Planetary scientists think that this chemical make-up is similar to Earths primordial atmosphere.

In a new study, University of Tokyos Dr. Takahiro Iino and colleagues used ALMA to study the chemical processes in Titans atmosphere.

The researchers detected faint but firm signals of two organic compounds acetonitrile (CH3CN) and its rare isotopomer CH3C15N in the ALMA data.

We found that the abundance of 14N in acetonitrile is higher than those in other nitrogen bearing species such as HCN and HC3N, Dr. Iino said.

It well matches the recent computer simulation of chemical processes with high energy cosmic rays.

There are two important players in the chemical processes of the atmosphere: ultraviolet (UV) light from the Sun and cosmic rays from beyond the Solar System.

In the upper atmosphere, UV light selectively destroys nitrogen molecules containing 15N because the UV light with the specific wavelength that interacts with 14N is easily absorbed at that altitude, the study authors explained.

Thus, nitrogen-bearing species produced at that altitude tend to exhibit a high abundance of 15N.

On the other hand, cosmic rays penetrate deeper and interact with nitrogen molecules containing 14N.

As a result, there is a difference in the abundance of molecules with 14N and 15N.

The team revealed that acetonitrile in the stratosphere is more abundant in 14N than those of other previously measured nitrogen-bearing molecules.

We suppose that galactic cosmic rays play an important role in the atmospheres of other solar system bodies, said Dr. Hideo Sagawa, a researcher at Kyoto Sangyo University.

The process could be universal, so understanding the role of cosmic rays in Titan is crucial in overall planetary science.

A paper on the findings will be published in the Astrophysical Journal.

_____

Takahiro Iino et al. 2020. 14N/15N isotopic ratio in CH3CN of Titans atmosphere measured with ALMA. ApJ, in press; arXiv: 2001.01484

Excerpt from:

Cosmic Rays from beyond Solar System Affect Atmosphere of Titan | Astronomy - Sci-News.com

Last night at 11:03 p.m. EST, the European Space Agency (ESA) and NASA successfully launched their joint Solar Orbiter mission from Cape Canaveral Air Force Station in Florida, with the spacecraft catching a ride aboard a United Launch Alliance Atlas V rocket.

During its mission, the Solar Orbiter will get up close and personal with the Sun in order to investigate our host star and its magnetic field, as well as how the Sun influences our solar system as a whole. Though the spacecraft will spend a few years easing into its unique elliptical orbit around the Sun, once there, it will be well positioned to also study the Suns poles up close for the first time.

Equipped with a camera, the orbiter's special orbit which occasionally takes it closer to the Sun than Mercury ever gets will enable the spacecraft to snap the first ever photos of the Sun's poles. Over the course of its mission, researchers plan to have the Solar Orbiter make 22 close approaches to the Sun.

There are 10 different instruments onboard the orbiter that will collaboratively study the Sun, including a visible light telescope and tools to capture solar wind particles, dust, and cosmic rays.

As humans, we have always been familiar with the importance of the Sun to life on Earth, observing it and investigating how it works in detail, but we have also long known it has the potential to disrupt everyday life should we be in the firing line of a powerful solar storm, Gnther Hasinger, ESA director of Science, said in a NASA press release. By the end of our Solar Orbiter mission, we will know more about the hidden force responsible for the Suns changing behavior and its influence on our home planet than ever before."

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Solar Orbiter is on its way to study the Sun - Astronomy Magazine

Nigerias educational curricula entail a 9-year Basic Education Curriculum (six years in primary school and three years in junior secondary school) and three years in senior secondary school. According to the Nigerian Education Research and Development Council (NERDC), the Basic Education Curriculum was formulated towards the attainment of mathematical abilities and literacy competencies, and will also lay the foundation towards entrepreneurial and vocational skills acquisition as well as prepare the students for senior secondary education.

The goal of the curriculum structure for senior secondary schools is to allow the students to acquire technical skills, have an understanding of the increasing complexity of Technology as well as prepare them for higher education. However, these curricula do not in entirety explore certain areas of study which knowledge becoming more needed in the world. One of such areas is the study of Astronomy, but then theres also the question of why Astronomy as a subject should be introduced into the Nigerian education curricula for basic and secondary schools; the answer is not far-fetched.

Astronomy is the scientific study of the universe, celestial bodies, gas and dust within it. It is one of the oldest science fields that is deeply rooted in several cultures, African culture inclusive. It creates environmental awareness and enlightens humans about the universe.

An average human has a curious mind and always seeks to find an answer to every question. This trait is even more active in children and young adults. They always want to know more about the world around them. Common astronomy-related questions they ask are; why the stars twinkle, why some stars are so bright, where we came from, why is there so much we dont know about the universe, etc. Unfortunately, as they grow up and go through the school processes, the frame of school works and educational system begin to limit their curiosity as there is hardly any subject which embraces and provides the much-needed answers to these questions. Introduction of astronomy to children and young adults is one of the best ways of harnessing their curiosity.

Astronomy as an interesting subject can be taught in a series of indoor and outdoor sessions, and visitations to interesting places. Through movies, slides, moon observations, watching sunspots, visiting planetarium and observatories, children are exposed to opportunities to explore, thereby nurturing their curiosity and propensity for invention.

Also, incorporating astronomy into the secondary school curriculum will give a more interesting approach to some science subjects. Astronomers use mathematics and physics theories all the time, and this has influenced the development of some branches of Physics and Mathematics such as Trigonometry, Calculus, Logarithm, Gravity, etc.

According to Edutopia, relating things that are usually boring and difficult to that which arouses their curiosity, will make students more capable of learning. For example, explaining to a science student how Pythagoras Theorem, Trigonometry and Parallax method is used to calculate the distance of a particular star or star cluster to the earth helps the student better remember how to solve the problem in the future.

At the senior secondary level, Geography was added to the curriculum so the students can learn about the human environment. But, Geography is limited to the study of the physical properties of the earth, places on earth and human interactions with it while Astronomy encompasses the study of the whole universe. Geography is therefore not a substitute for Astronomy as some may perceive.

Astronomy is sometimes too abstract and complicated, as some people may say. Yes! It is, but there is nothing too complex to be broken into bits. Introduction to spatial thinking at this early stage will certainly capacitate students with the ability to think outside the box.

Furthermore, space technology is a branch of astronomy that deals with the exploration of outer space, and includes spaceflight, and development of satellites. Satellite technology has helped to improve the quality of life on Earth. There are different types of satellites, and each is launched for a specific purpose. In Africa, satellites launched so far have been useful for earth observation, communication and other developmental purposes. Satellite coverages have offered fact-based viewpoints that have helped overcome our eminent challenges and will continue to do so much more in the future. Earth-imaging satellites have been improving our agricultural yields, food security, disaster monitoring, wildlife protection, and can reduce or eliminate terrorism. Ultimately, satellite technology contributes immensely to the economic development of a nation.

According to Space in Africa, Space science and technology in Africa set lots of new records in 2019. In 2019 alone, eight satellites were launched by five different countries in Africa. These are signs of economic growth.Now, how many of the younger generations are aware of these developments, and are looking forward to having a career in this field? How will these happen if they are not allowed to know about Astronomy before they reach the stage where their interests get narrowed down? Most Nigerian Astronomy students encountered this field when they were enrolling to study in higher institutions. Adaptation to the course was, therefore, not smooth because of the lack of prior knowledge.

Interestingly, students can still go on to study other courses in higher institutions like mechanical engineering, biology, chemistry, history, language arts, law, etc., and still participate in the advancement of space science and technology in Africa. How? Because astronomy is one of the most interdisciplinary course there is.

With the international effort to build the worlds largest radio telescope SKA (Square Kilometre Array) across select countries in Africa, expertise in several fields like data analysis, development of supercomputers, etc. will be needed. For indigenous youths to be competent enough to fit into these positions and participate in this field, exposure to at an early stage is vital.

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Benefits Of Astronomy As A Subject In Primary And Secondary Schools Curricula - Space in Africa

Monday, February 10Mercury climbs to its maximum altitude in the evening sky tonight, when it lies some 11 high in the west-southwest 30 minutes after sunset. This peak coincides with the planet reaching its greatest elongation from the Sun. Mercury shines at magnitude 0.6, so it should be easy to spot in the deepening twilight. If you cant see it with your naked eye, binoculars will show it easily. Target the planet through a telescope and you will see a 7"-diameter disk that appears half-lit.

Tonight may be your last best chance to track down Neptune during its current apparition. The outermost major planet glows at magnitude 8.0, so youll need to wait until darkness falls and then use binoculars or a telescope to find it. Neptunes low altitude it lies barely 8 above the western horizon as twilight ends only adds to the challenge. What makes tonight so appealing for a planet quest is that the ice giant world skims just 2' north of the 4th-magnitude star Phi () Aquarii. Thats about the separation between Io and Jupiter when the innermost jovian moon reaches greatest elongation. To confirm a Neptune sighting, aim a telescope at your suspected target. Only the planet shows a 2.2"-diameter disk and subtle blue-gray color.

The Moon reaches perigee, the closest point in its orbit around Earth, at 3:28 p.m. EST. It then lies 223,980 miles (360,461 kilometers) away from us.

Tuesday, February 11Tonight should provide your first good opportunity of 2020 to view the zodiacal light. From the Northern Hemisphere, late winter and early spring are the best times of year to observe this elusive glow after sunset. It appears slightly fainter than the Milky Way, so youll need a clear moonless sky and an observing site located far from the city. With the waning gibbous Moon now exiting the early evening sky, the next two weeks will be prime viewing times. Look for the cone-shaped glow, which has a broad base and points nearly straight up from the western horizon, after the last vestiges of twilight have faded away.

Wednesday, February 12Ruddy Mars continues to grace the predawn sky this week. The Red Planet now rises before 4 a.m. local time and climbs 20 above the southeastern horizon an hour before sunrise. Mars glows at magnitude 1.3 against the backdrop of Sagittarius the Archer, having crossed the border from Ophiuchus the Serpent-bearer just yesterday. Although the passage from Ophiuchus into Sagittarius is little more than a technical milestone, it does set up a series of pretty conjunctions with some of the Archers deep-sky gems next week. Unfortunately, a telescope doesnt add much to our current view of the planet, revealing a bland disk that measures just 5" across.

Thursday, February 13Although Saturn passed on the opposite side of the Sun from Earth only a month ago, it already appears low in the southeast before dawn. Look for the magnitude 0.6 ringed planet some 10 to the lower left of brilliant Jupiter. Saturns low altitude means it wont look like much through a telescope, though that will change in the coming months.

Friday, February 14In what seems a fitting tribute, the planet named after the Roman goddess of love shines brilliantly in the evening sky on Valentines Day. Venus gleams at magnitude 4.2 and shows up easily in the west-southwest within a half-hour after sunset. It grows even more prominent as darkness settles over the landscape. The planet doesnt set until a bit after 8:30 p.m. local time. If you turn a telescope on Venus, youll see a disk that spans 17" and appears about two-thirds lit.

Saturday, February 15Last Quarter Moon occurs at 5:17 p.m. EST. Look for it either before dawn this morning (when it lies among the background stars of Libra and looks slightly more than half-lit) or after it rises around 1:30 a.m. local time tomorrow (when it stands against the backdrop of northern Scorpius and appears as a fat crescent).

Continued here:

The Sky This Week from February 7 to 16 - Astronomy Magazine

Using data from NASAs Kepler/K2 mission and several ground-based instruments, astronomers have discovered a planetary system with three transiting planets around the 9-billion-year-old star EPIC 249893012.

An artists impression of the EPIC 249893012 planetary system. Image credit: Sci-News.com.

EPIC 249893012 is a G8-type evolved star located approximately 1,057 light-years away from Earth.

Also known as 2MASS J15125956-1643282 or TYC 6170-95-1, the star is 71% larger than the Sun, but has a mass of just 1.05 times solar.

EPIC 249893012, which is approximately 9 billion years old, hosts at least three massive planets.

The inner planet is a hot super-Earth with an orbital period of 3.6 days.

Named EPIC 249893012b, the alien world is 1.95 times bigger than Earth and 8.75 times more massive.

EPIC 249893012b is a super-Earth with a density compatible with a pure silicate composition. However, a more realistic configuration would be a nickel-iron core and a silicate mantle, said Diego Hidalgo from the Instituto de Astrofisica de Canarias and the Universidad de La Laguna, Tenerife, and his colleagues.

The planet has some residual hydrogen-helium atmosphere, which enlarges its radius but does not significantly contribute to the total planet mass.

Planets EPIC 249893012c and d are warm sub-Neptunes with orbital periods of 15.6 and 35.7 days, respectively.

They have masses and radii of 14.67 Earth masses and 3.67 Earth radii and 10.2 Earth masses and 3.94 Earth radii.

The three new planets were first discovered in data from the Kepler/K2 mission.

Hidalgo and co-authors then confirmed the discovery using the InfraRed Camera and Spectrograph (IRCS) on the 8.2-m Subaru Telescope, the High Accuracy Radial velocity Planet Searcher (HARPS) spectrograph at the 3.6-m telescope of ESOs La Silla Observatory, and the HARPS-N spectrograph at the 3.58-m Telescopio Nazionale Galileo at Roque de Los Muchachos Observatory.

Combining K2 photometry with high-resolution imaging and high-precision Doppler spectroscopy, we confirmed the three planets and determined their masses, radii, and mean densities, the astronomers explained.

Because the EPIC 249893012 system is at an early stage of its evolution after leaving the main sequence, it is a good candidate for a detailed study of its dynamical evolution to (i) shed light on the formation of close-in giant planets, and (ii) test a hypothesis that giant planets form a dynamical barrier that confines super-Earths to an inward-migrating evolution, they said.

The teams paper was published in the journal Astronomy & Astrophysics (arXiv.org preprint).

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D. Hidalgo et al. 2020. Three planets transiting the evolved star EPIC 249893012: a hot 8.8-MEarth super-Earth and two warm 14.7 and 10.2-MEarth sub-Neptunes. A&A, in press; doi: 10.1051/0004-6361/201937080

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Astronomers Find Three Massive Exoplanets Orbiting Evolved Star | Astronomy - Sci-News.com

Astronomers have found a monster galaxy causing trouble in the early Universe.

When the Universe was just 1.8 billion years old, galaxy XMM-2599 was already a colossal chonker. It was also already dead as a doornail.

Sometime between the Big Bang (13.8 billion years ago) and 12 billion years ago, it had ballooned out in a burst of star formation - and then completely stopped.

"Even before the Universe was 2 billion years old, XMM-2599 had already formed a mass of more than 300 billion suns, making it an ultramassive galaxy," said physicist and astronomer Benjamin Forrest of the University of California, Riverside.

"More remarkably, we show that XMM-2599 formed most of its stars in a huge frenzy when the Universe was less than 1 billion years old, and then became inactive by the time the Universe was only 1.8 billion years old."

For a long time, astronomers thought giant galaxies couldn't form in the early Universe. As our technology advanced, and we grew better at peering into those far reaches of space-time, those assumptions have been challenged.

It turns out the early Universe was swimming withmassive things that, according to our cosmological models, shouldn't have had time to grow. Numerical models can now account for massive galaxies like XMM-2599.

But something that got so large so quickly and then just stopped growing all of a sudden? That's a whole 'nother kettle of weird.

XMM-2599 is not the first. A few years ago, astronomers found a massive galaxy called ZF-COSMOS-20115 that had burst into life, then stopped suddenly by the time the Universe was 1.7 billion years old. ZF-COSMOS-20115, however, was 'only' 170 billion solar masses - just over half the mass of XMM-2599.

"In this epoch, very few galaxies have stopped forming stars, and none are as massive as XMM-2599," said physicist and astronomer Gillian Wilson of UC Riverside.

"The mere existence of ultramassive galaxies like XMM-2599 proves quite a challenge to numerical models. Even though such massive galaxies are incredibly rare at this epoch, the models do predict them. The predicted galaxies, however, are expected to be actively forming stars.

"What makes XMM-2599 so interesting, unusual, and surprising is that it is no longer forming stars, perhaps because it stopped getting fuel or its black hole began to turn on. Our results call for changes in how models turn off star formation in early galaxies."

Based on spectroscopic observations taken of the galaxy, the research team were able to piece together XMM-2599's star formation history. In order to get so huge, it would've had to have been forming stars at a rate of 1,000 solar masses every year for around 500 million years, at the peak of its starburst activity.

The Milky Way's star formation rate, for context, is currently around three or four solar masses per year.

Although high, XMM-2599's peak star formation rate is not unique for its time period. In 2008, a galaxy called EQ J100054+023435 was caught churning out stars at a rate of over 1,000 solar masses per year, 12.2 billion years ago. It, however, like ZF-COSMOS-20115, was much less massive than XMM-2599, at just 10 billion solar masses. And it wasn't dead.

In the past few years, simulation software has improved a great deal, and can account for extreme star formation in the early Universe. But it can't yet produce conditions that result in dead massive galaxies - what we see in ZF-COSMOS-20115 and XMM-2599.

So, there's plenty of question marks over XMM-2599. Did it form from a bunch of other galaxies? What turned it off?

And what did it evolve into in the 12 billion years since its light started its long journey across the Universe? Did it stay dead? Did it flare back to life, like the Milky Way? Or did something else happen?

"We have caught XMM-2599 in its inactive phase," Wilson said.

"We do not know what it will turn into by the present day. We know it cannot lose mass. An interesting question is what happens around it. As time goes by, could it gravitationally attract nearby star-forming galaxies and become a bright city of galaxies?"

Space, man. It's freaking nuts.

The research has been published in The Astrophysical Journal Letters.

See more here:

Astronomers Find Ultramassive Galaxy From The Early Universe That Suddenly Died - ScienceAlert

Before Starlink launched, SpaceX coordinated with the National Science Foundation and its radio-astronomy observatories to make sure there wouldnt be any overlap. Unfortunately for optical astronomers, there is no such framework when it comes to the brightness of satellitesno international body in Geneva, let alone a dedicated agency in the United States. The Federal Communications Commissions regulatory realm spans communication networks across multiple industries, which means its oversight includes, oddly enough, both satellites and offensive Super Bowl commercials. But while American satellites need the agencys permission to launch, the FCC does not regulate the appearance of those satellites once theyre in orbit.

Read: The dark side of light

From the ground, Starlink satellites appear as points of light moving from west to east, like a string of tiny pearls across the dark sky. (Some people have even mistaken them for UFOs.) The satellites are at their brightest after launch, before they spread out and rise in altitude, and are visible even in the middle of cities. They appear dimmer after a few months, when they reach their final orbit, about 342 miles (550 kilometers) up, but even then they can still be seen in darker areas, away from the glare of light pollution.

In the months since they first launched, the Starlink satellites have been essentially photobombing ground-based telescopes. Their reflectiveness can saturate detectors, overwhelming them, which can ruin frames and leave ghost imprints on others. Vivienne Baldassares work depends on comparing images taken night after night and looking for nearly imperceptible variations in light; the slightest shifts could reveal the existence of a black hole at the center of a glittering, distant galaxy. Baldassare, an astronomer at Yale, cant see behind the streak of a satellite. You cant just subtract that off, she says. Some objects, such as comets, are better viewed during dawn and dusk, when theres just enough sunlight to illuminate them. But because they orbit close to Earth, the Starlink satellites can be seen during these hours, too; imagine missing a comet as it passes uncomfortably close to Earth because of too many satellites.

SpaceX is actively working with leading astronomy groups from around the world to make sure their work isnt affected, says the companys spokesperson, James Gleeson. To that end, one satellite in a batch of 60 launched in early January with experimental coating that might make it less reflective. Engineers wont know how well it worked until the satellite reaches its final orbit.

As it waits for those data, SpaceX has continued to launch dozens of the original satellites. The company wants to deploy more than 1,500 satellites in 2020 alone, which means launches could come every few weeks. On top of those, the company OneWeb is scheduled to launch a batch of its own internet satellites this week; the proposed constellation of about 650 will fly at higher altitudes, which might have the paradoxical effect of being too dim to see from the ground but bright enough for telescopes to spot well into the night. And Jeff Bezoss Amazon has asked the FCC for permission to someday launch a network of 3,200 internet satellites. In a few years time, three companies alone might transform the space around Earth, with SpaceX leading the pack.

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The Night Sky Will Never Be the Same - The Atlantic

A recently discovered fast radio burst turns out to be pulsing on a steady 16-day cycle, marking the first time scientists have been able to see a specific tempo from one of these mysterious signals.

Whats an FRB? They are extremely powerful radio emissions lasting only a few milliseconds. The sources of these bursts are absolute mysteries to astronomers, and of the hundreds that have been detected so far, weve only localized where five actually come from. Whatever event produces these emissions generates over tens of thousands of times more energy than the sun. While most FRBs are one-off signals, a few have been detected multiple times overagain, without explanation. Scientists have batted around hypotheses ranging from cosmic collisions to stellar flares to highly magnetized neutron stars to intelligent extraterrestrials (well come to that).

What do we know about this FRB? Its a repeating burst calledFRB 180916.J0158+65, first detected on September 16, 2018. It comes from a massive star-forming spiral galaxy 500 million light-years away, rich in heavy metals and low in magnetism.

Whats new here: After initially discovering FRB 180916.J0I158+65, the Canadian Hydrogen Intensity Mapping Experiment (CHIME) in British Columbia began follow-up observations for 13 months, detecting 28 more bursts. The bursts arrived in four-day phases (sometimes with multiple bursts, sometimes without bursts) followed by 12 days of silence, indicating that the source producing the FRB operated on a regular 16-day cycle. The findings were reported in a new paper recently uploaded to arXiv.

The plot thickens: The fact that the FRB has an overall 16-day cycle but the four-day window varies between zero signals and multiple signals suggests the source might be orbiting a massive object of some kind (such as low-mass black hole) that perhaps stimulates or eclipses emission of the signal based on the orbital period. A separate study posits that the FRB is produced by a neutron star in a binary system with a much more massive star.

Wait, is it aliens? Almost certainly not. The signals are a sign of energetic events that are on the extreme scale of the cosmos. Even a highly intelligent species would be very unlikely to produce energies like this. And there is no detectable pattern so far that would suggest theres a sentient hand at play.

See the article here:

Astronomers have found a deep space radio burst that pulses every 16 days - MIT Technology Review

Fast radio bursts can emit as much power as hundreds of millions of suns but only last a few milliseconds, making them difficult to study, until now. Buzz60

For the first time, scientists have detected a radio signal from outer space that repeatsat regular intervals.

The series of "fast radio bursts" short-lived pulses of radio waves that come from across the universe were detected about once an hour for four days and then stopped,only to start up again 12 days later.

This cycle repeated every 16.35 days for more than a year, according to a new paper about the research.

The bursts originated from a galaxy about500 million light-years away.

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"The discovery of a 16.35-day periodicity in a repeating FRB source is an important clue to the nature of this object," the scientists said in the paper.

An artist's conception of how ground-based telescopes detected a "fast radio burst" from a distant galaxy.(Photo: CSIRO/Andrew Howells)

The repeating pattern, reports Science X Network, "suggests the source could be a celestial body of some kind orbiting around a star or another body. In such a scenario, the signals would cease when they are obstructed by the other body."

"But that still does not explain how a celestial body could be sending out such signals on a regular basis," Science X said. "Another possibility is that stellar winds might be alternately boosting or blocking signals from a body behind them. Or it could be that the source is a celestial body that is rotating."

Alien signals?More bizarre 'fast radio bursts' detected from outer space

It's not likely to be aliens, the Massachusetts Institute of Technology said in a statement, because the signals are a sign of energetic events that are on the extreme scale of the cosmos. "Even a highly intelligent species would be very unlikely to produce energies like this. And there is no detectable pattern so far that would suggest theres a sentient hand at play," MIT said.

Fast radio bursts last only a few milliseconds, which makes it difficult to accurately determine where they have come from.

"One of the greatest mysteries in astronomy right now is the origin of short, dramatic bursts of radio light seen across the universe," the Max Planck Institute for Radio Astronomysaid in a statement.

"Although they last for only a thousandthof a second, there are now hundreds of records of these enigmatic sources," the institute said.

Since 2007, according to MIT, most of the radio bursts are one-offs, but a small number are repeaters which recur in the same place.

Thefast radio burst that repeats every 16 days was detected by the Canadian Hydrogen Intensity Mapping Experiment, a radio telescope designed and built by several groups of Canadian scientists to study space phenomena.

#BroomChallenge: You can actually stand a broom up anytime during the year

You may like: NASA astronaut Christina Koch returns to Earth after recording-setting 328 days in space

The CHIME telescope in British Columbia will help detect future fast radio bursts.(Photo: Andre Recnik)

Read or Share this story: https://www.usatoday.com/story/news/nation/2020/02/12/fast-radio-burst-signal-outer-space-repeats-every-16-days/4726301002/

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Scientists detect an unexplainable radio signal from outer space that repeats every 16 days - USA TODAY

Actress, neuroscientist, and overall genius Mayim Bialik will use her science know-how LEGO Masters

This weeks highly-anticipated Space Smash event aims to be an astronomical, televised brick build-off.

LOS ANGELES - Following last weeks amusement park-themed episode of LEGO Masters, this weeks highly-anticipated Space Smash event aims to be an astronomical, televised brick build-off.

If that werent exciting enough, actress, neuroscientist, and overall genius Mayim Bialik will use her science know-how as a guest judge, critiquing the LEGO-ized aliens, rocket ships and more.

To get you stoked for Wednesday nights episode, here are some LEGO facts that are simply out of this world:

Each year, over 20 billion LEGO pieces are made

There are approximately 35,000 LEGO pieces made every single minute. That might explain why its so easy to step on them.

Since LEGO began production of its iconic colorful pieces in 1932, there have been 400 billion created. If you stacked together every brick ever produced, the resulting toy tower would be 2,386,065 miles tall.

LEGO = Play Well

The name LEGO originates from the Danish term Leg Godt, meaning Play Well. Its actually the companys motto.

Every second, seven LEGO sets are sold in retail

The toy has never slowed in demand since the Danish company began making sets in 1955.

As if these brick production efforts werent impressive enough, LEGO also makes 400 million tiny toy tires annually, technically making the company the largest tire manufacturer in the world.

There are 86 LEGO bricks for every person on Earth

And for some, they have their own LEGO-ized versions of themselves. The manufacturer started basing its figurines off of notable people when it began producing NBAMinifigures in 2003.

The plural of LEGO is LEGO

The companys famous bricks come in over 60 different colors. This explains why it is so easy to get creative with them.

Each piece even has its own story. On the interior of a LEGO brick is stamped a three-digit number that indicates the origin of the molds production line. This means that any brick could be traced back to where it was produced in the event of errors.

Watch LEGO Masters at 9 p.m. ET / 6 p.m. PT on FOX.

This story was reported from Los Angeles. This station is owned by the FOX Corporation.

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Here are some astronomical LEGO facts in honor of LEGO Masters upcoming space-themed episode - FOX 10 News Phoenix

The world economy depends on nature, from coral reefs that protect coastal cities from flooding to insects that pollinate crops. But by the middle of the century, the loss of key ecosystem services could cost the world $479 billion each year. The U.S. will lose more than any other country, with an $83 billion loss to the GDP per year by 2050.

Thats a conservative estimate. The projection comes from a report, called Global Futures, from World Wildlife Fund, which looked at only six of the services that nature provides and how those might change because of the impacts of climate breakdown, lost wildlife habitat, and other human-caused destruction of nature. (Many other services will also be impacted but cant currently be accurately modeled; the study also doesnt take into account the possibility of tipping points that lead to sudden, catastrophic losses of natural services.) By 2050, if the world continues on its current path, the global economy could lose $327 billion a year as we lose natural coastal protection from coral reefs, mangrove forests, and other natural systems. Another $128 billion could be lost annually from forests and peatlands that store carbon. Agriculture could lose $15 billion from lost pollinators and $19 billion from reduced water availability. Food costs are likely to go up, threatening food security in some regions.

In the U.S., the biggest losses will come from lost coastal protection and losses in marine fisheries. Because of the size of the U.S. economy, it will lose most in absolute terms. But developing countries will be hit hardest in terms of the percentage of GDP lost; Madagascar tops that list, followed by Togo, Vietnam, and Mozambique.

If the world radically changes course to more sustainable development, protecting areas that are most critical for biodiversity and ecosystem services, the global annual GDP could, instead, grow $11 billion by 2050. Businesses can help this happen by taking steps to make sure their supply chains arent damaging tropical forests and other key ecosystems, the report says. The nonprofit is also advocating for a New Deal for Nature and People that would help stop and reverse biodiversity loss by 2030. The current situation is bleak: Around half of the worlds corals have been lost in the last three decades. An average of around 12 million hectares of tropical forest has been lost each year in the last decade. More than 40% of insect species are at risk of extinction in the next few decadesand overall, a U.N. report last year estimated that humans have managed to put more than 1 million species at risk of extinction.

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The economic cost of destroying nature is astronomical - Fast Company

A "supermoon" is seen over Dubai, United Arab Emirates, on Nov. 14, 2016.

Come Sunday night, and a larger-than-usual full moon is likely to greet you with the decade's first supermoon-like experience. While most of the astronomers believe that the full snow moon on February 9 is a supermoon, there are a few who say it is not. Remember, there is no single foolproof definition for the supermoon, and hence the confusion.

Amid all the ambiguity, we asked Mr Pradeep Nayak, a senior astronomer at Khagol Mandal and the author of 'Tarangan: Guide to night sky', to answer to tell us more about this recurring phenomenon. Khagol Mandal is a non-profit collective of astronomy enthusiasts who organise various sky observation programmes, lectures and study tours. Here is what Mr Nayak had to say:

First, can you tell us what a supermoon is?

A 'supermoon' rises at CST in Mumbai on Monday, November 14, 2016,

Supermoon simply means the full moon which appears larger to us than usual when its position in its orbit is nearest to the Earth. According to another definition, it is also the new moon at its closest approach to Earth, but since the new moon is 'Amavasya', we cannot observe the moon that day. There is no official definition of supermoon given by the International Astronomical Union. So, one may find different full moons or new moons as supermoons.

On February 9, there is a full moon day, and it's also a 'supermoon' according to famous Solar and Lunar eclipse scientist, Fred Espenak.

What is the best time and place to witness the supermoon on February 9?

As the sun will set in the west, this supermoon will rise over the eastern horizon. Choose a place from where the eastern horizon is clearly visible. Moon will rise at around 7:10 from Mumbai region. Since our celestial neighbour will be visible throughout the night, you can get a glimpse of brighter and larger than usual supermoon any time during the night. As the moon rises high on the sky, one can witness moon from any suitable place. It might be cold out there. So if you are planning to stay outdoor for a longer time, it is better to protect yourself with warm clothing.

Will the supermoon be visible around the world?

A "super moon" rises near the Lincoln Memorial on March 19, 2011, in Washington, D.C.

As Earth rotates around its axis in 24 hours, entire Earth will be able to observe the full moon on this day. As the day starts from the east, from the International Date Line, the night also starts from there.

Supermoon will be visible to half of the globe at a time. During the nighttime, all seven billion-plus people will be able to watch brightly lit supermoon, provided the sky clear. As the moon approached its 'perigee' with respect to Earth, the apparent size would be larger than usual.

Wait a minute, what do you mean by the 'perigee', and how much do supermoon events vary in size and brightness?

Moon is the most prominent object in the sky. Moon is the closest celestial object to us. Lying at the average distance of 3,84,000 km from Earth, it revolves the Earth about every 27 days.

To understand what is apogee and perigee, we have to remember what we studied during high school. Every planet revolves around the sun in an elliptical orbit, and every ellipse has two foci, i.e., two centres. Sun is on one of the foci. So, when the planet revolves around the sun, planet-sun distances are not constant, but always change. Hence, during the revolution, at one point in its orbit, the planet comes closest to the sun and at another point planet moves farthest from the sun.

Mumbaikars were treated with a bigger and brighter super full moon on Tuesday, Feb 19, 2019.

Same is true for our earth-moon system. When the moon is farthest to Earth in its orbit, at the distance of 4,05,700 km, i.e. 21,700 km further than average, it appears slightly smaller in apparent size. This point on moon's orbit is called as 'apogee'.

When the moon is closest to the Earth in its orbit, it is at the distance of 3,63,100 km from Earth, which is almost 21,000 km closer than the average. At this point, called 'perigee', the moon appears much larger.

Whenever the full moon occurs at or near perigee, it is called 'supermoon'. A supermoon appears around 14 per cent larger and 30 per cent brighter than usual. Of course, the change in size and brightness is not distinctly perceivable to a casual observer. With sophisticated instruments and accurate measurements, one can measure the difference in size as well as brightness.

Is there any impact of this particular phase of the moon on the Earth?

The term supermoon is relatively new. A US astronomer by the name Richard Nolle coined this term about 40 years ago. There are a few predictions of disasters during supermoon day. But, these claims are entirely untrue and have been refuted by scientists all over the world. It is the day as usual for Earth. Apart from a visual treat, the only effect we may observe is slightly higher spring tide. Astronomy enthusiasts now use this event to popularise astronomy.

How many supermoons can we look forward to in 2020?

"Supermoon" appears in the sky over Cairo, Egypt, on Jan. 31, 2018.

In the recent past, there were three consecutive supermoons in October, November and December 2016, which arouse the interest of people all over the world. November 2016 was the largest supermoon in the last 70 years.

The year 2020 is unique in terms of lunar events as we are going to witness four consecutive supermoons: February 9, March 9, April 8 and May 7.

Why the apparent size of the moon visible from the Earth change with time?

As the moon revolves around the Earth in an elliptical orbit, the distance between the Earth and the moon keeps changing. Therefore, the size of the moon also varies according to distance.

There is another factor which changes the size of the moon with timealbeit extremely slowly. The gravitational interaction between the sun, the Earth and the moon, is slowly pulling the moon away from the Earth, at the rate of about 4 cm per year.

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This article was produced in collaboration with Khagol Mandal.

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Ask An Astronomer: Here's All You Need to Know About Decade's First Supermoon on February 9 - The Weather Channel

From the Atlantic Coast to the mountains, there's a lot to do and see in Georgia. On Fridays, Anchor and Reporter Suzanne Lawler is taking you into wild places around the state you've probably never been to in her four-part series "Georgia Adventures."

If you're into stargazing, the darkest city in the state and even the southeast has you covered.

Sharon, Georgia in Taliaferro County is what you would call a one-horse town, with a population just over a hundred folks.

"Sharon, at one time, had over 40 stores here, and with the end of cotton and people moving away to find jobs in the city and so on, it died," said Renee Brown.

She's the mayor.

"We have no business, and there are no commercial lights," Brown said.

The skeletons of the past still stand, but there is a silver lining.

"I grew up in Atlanta, and I never really thought about astronomy and the stars and so on, and you come out here, and look at the sky at night, and it's another world, and it's fascinating, and it's beautiful," she said.

RELATED: Off the Beaten Path: Lake Tchukolako in Wilkinson Co.

In 2006, a group of folks from Atlanta bought a large tract of land and named it the Deerlick Astronomy Village.

"I always tell people that it's astronomy, not astrology. We are not the people that dance naked in front of the moon; we just are semi-scientists," said Jane Kuehn, who lives at the village.

Folks that live out there take star gazing seriously. There are 26 plots of land that cost homeowners at least $35,000 a piece.

"This is the darkest city in Georgia, and it's probably the darkest city in the southeast," Kuehn said.

Many homes have retractable roofs.

"This one you're pointing at here is a Richie Crichton telescope, I do mainly imaging, so you see the main telescope here here, it's a 10-inch, which basically means you have a 10-inch diameter mirror in the back," Daniel Ford said.

Ford took up astronomy as a kid, and as an imager, he's able to capture the moon in all its glory.

"So you see quite a number of the craters as well as the seas," Ford said.

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Dan Llewellny is a deep space imager too, and his photographs are stunning.

"This is where a lot of the new stars are born, there's all sorts of stellar nurseries all throughout the galaxy," Llewellny said.

Llewellny sends his stellar images to NASA.

"This is Messier 31, which is our neighboring galaxy," he said.

Where there's galaxies, there's planets.

"This is the Great Red Spot. The Great Red Spot is a giant storm on Jupiter. The diameter of the great red spot will fit two earths in here," Llewellny said.

These guys use really expensive equipment, but you can achieve this image with a DSLR camera or a high-end still photography camera.

The village does have two open houses a year for you to check them out. No matter what kind of gear you bring, there is a magic to seeing the night sky like few have ever seen it.

"You feel sort of really connected to the universe," he said.

You can learn more about the Deerlick Astronomy Village on their website.

Check out the last Georgia Adventures story, where Suzanne headed out to rural Georgia for a guided, high-tech hog hunt.

RELATED: How you can go on a guided, high-tech hog hunt

Join us next Friday, Feb. 14 on 13WMAZ Morning at 6 a.m., where Suzanne checks out one of the Seven Natural Wonders of Georgia.

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Darkest county in Georgia has its own astronomy village - 13WMAZ.com