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Pinning down the suns birthplace just got more complicated – Science News

The sun could come from a large, loose-knit clan or a small family thats always fighting.

New computer simulations of young stars suggest two pathways to forming the solar system. The sun could have formed in a calm, large association of 10,000 stars or more, like NGC 2244 in the present-day Rosette Nebula, an idea thats consistent with previous research. Or the sun could be from a violent, compact cluster with about 1,000 stars, like the Pleiades, researchers report July 2 in the Astrophysical Journal.

Whether a star forms in a tight, rowdy cluster or a loose association can influence its future prospects. If a star is born surrounded by lots of massive siblings that explode as supernovas before a cluster spreads out, for example, that star will have more heavy elements to build planets with (SN: 8/9/19).

To nail down a stellar birthplace, astronomers have considered the solar systems chemistry, its shape and many other factors. Most astronomers who study the suns birthplace think the gentle, large association scenario is most likely, says astrophysicist Fred Adams of the University of Michigan in Ann Arbor, who was not involved in the new work.

But most previous studies didnt include stars motions over time. So astrophysicists Susanne Pfalzner and Kirsten Vincke, both of the Max Planck Institute for Radio Astronomy in Bonn, Germany, ran thousands of computer simulations to see how often different kinds of young stellar families produce solar systems like ours.

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The main solar system feature that the pair looked for was the distance to the farthest planet from the star. Planet-forming disks can extend to hundreds of astronomical units, or AU, the distance between the Earth and the sun (SN: 7/16/19). Theoretically, planets should be able to form all the way to the edge. But the suns planetary material is mostly packed within the orbit of Neptune.

You have a steep drop at 30 AU, where Neptune is, Pfalzner says. And this is not what you expect from a disk.

In 2018, Pfalzner and her colleagues showed that a passing star could have truncated and warped the solar systems outer edge long ago. If thats what happened, it could help point to the suns birth environment, Pfalzner reasoned. The key was to simulate groupings dense enough that stellar flybys happen regularly, but not so dense that the encounters happen too often and destroy disks before planets can grow up.

We were hoping wed get one answer, Pfalzner says. It turned out there are two possibilities. And they are wildly different from each other.

Large associations have more stars, but the stars are more spread out and generally leave each other alone. Those associations can stay together for up to 100 million years. Compact clusters, on the other hand, see more violent encounters between young stars and dont last as long. The stars shove each other away within a few million years.

This paper opens up another channel for what the suns birth environment looked like, Adams says, referring to the violent cluster notion.

The new study doesnt cover every aspect of how a tight cluster could have affected the nascent solar system. The findings dont account for how radiation from other stars in the cluster could erode planet-forming disks, for example, which could have shrunk the suns disk or even prevented the solar system from forming. The study also doesnt explain certain heavy elements found in meteorites, which are thought to come from a nearby supernova and so could require the sun come from a long-lived stellar family.

I think [the research] is an interesting addition to the debate, Adams says. It remains to be seen how the pieces of the puzzle fit together.

Pfalzner thinks that the star cluster would break apart before radiation made a big difference, and there are other explanations for the heavy elements apart from a single supernova. She hopes future studies will be able to use that sort of cosmic chemistry to narrow the suns birthplace down even further.

For us humans, this is an important question, Pfalzner says. Its part of our history.

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Pinning down the suns birthplace just got more complicated - Science News

Spectacular stars in the Astronomy Photographer of the Year shortlist – New Atlas

The Insight Investment Astronomy Photographer of the Year is one of the worlds top astrophotography competitions, and the 2020 shortlist offers a sublime selection of this years best entries, from some mind-bending close-ups of the suns surface to a series of magnificent Milky Way skyscapes.

The contest is run by the Royal Observatory Greenwich, an iconic scientific institution founded nearly 400 years ago. There are eight key categories in the contest, spanning a broad spectrum of astrophotography styles, from skyscapes incorporating land perspectives, to more focused categories looking at galaxies and aurorae.

BEN BUSH

As with previous years, the contest illustrates the incredible skill and determination these photographers display to create these images. UK photographer Ben Bushs shot of an aurora over Icelands famous Vestrahorn is a great example. To get the perfect shot of the aurora reflecting over the water, Bush waded out into the freezing North Atlantic ocean in the middle of night.

Mathew Browne

Other shortlisted images highlight the patience and timing needed to compose the ideal frame. Matthew Browns shot of the Moon passing behind Londons Shard skyscraper is an example of a fleeting moment in time that took the photographer days to catch.

Kirsty Paton

The winning photographs will be revealed later in the year, sharing 10,000 in prize money.

Take a look through our gallery at more shortlisted images from this years contest.

Source: RMG

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Spectacular stars in the Astronomy Photographer of the Year shortlist - New Atlas

Apollo-Soyuz Mission: When the Space Race Ended – Astronomy Magazine

A handshake in space

To some politicians, the ultimate symbol of dtente would be docking a Soviet capsule with an American one in low-Earth orbit for a handshake in space. Scientists and engineers saw benefits to such a joint mission, too. America had talented space pilots and advanced long-distance space technology. Meanwhile, the Soviets had focused on automation and had pioneered long-term spaceflights. Both had something the other was interested in learning about.

An American delegation traveled to Moscow in 1970 to lay the framework for the mission, and within two years, the Apollo-Soyuz Test Project was officially born.

But not everyone liked the idea. Each side worried the other could steal its technology. Some defense hawks, and even a New York Times editorial board opinion, noted that Apollo-Soyuz offered a technical and scientific bonanza for the Soviet Union's lagging astronautical program. Meanwhile, the Soviets continued insulting American spacecraft.

Finally, three years after the final Apollo moon flight, the two superpowers overcame the political and engineering hurdles to make the rendezvous happen, including the design and development of an American-funded docking module that could mate the two crafts.

On July 15, 1975, a Soyuz capsule and an Apollo capsule leftover from a canceled moon flight launched within hours of each other from opposite sides of the planet. Then, two days later, they met up 140 miles over Earths surface.

Soyuz and Apollo are shaking hands now, Soyuz commander Alexei Leonov said as the two spacecraft gently docked. And as the door opened between the ships, the astronauts inside exchanged their own handshakes and posed for pictures.

Over the next two days, the men learned to work together as they toured the other countrys spacecraft and carried out five joint scientific experiments. At first, though, they struggled to even communicate. Each wanted to speak their own language, but they eventually realized that they all understood things better when they attempted to speak the others language.

We [the Americans] thought they [the Soviets] were pretty aggressive people and ... they probably thought we were monsters, Brand said. So we very quickly broke through that, because when you deal with people that are in the same line of work as you are, and you're around them for a short time, why, you discover that, well, they're human beings."

Together, the crew helped their space agencies gather new technical and scientific insights. One experiment tested the effects of low-gravity on the development of fish eggs. Another created an artificial solar eclipse using the Apollo capsule to block the sun while cosmonauts took pictures of the solar corona.

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Apollo-Soyuz Mission: When the Space Race Ended - Astronomy Magazine

UNM astronomers on team revealing the magnetic field of a spiral galaxy – UNM Newsroom

Galaxies not only contain stars, gas, dust, and the mysterious Dark Matter, they are also magnetized. The magnetic fields are many orders of magnitude weaker than the Earth's field or a typical bar magnet, yet scientists can measure them with radio telescopes such as National Science Foundation's Karl G. Jansky Very Large Array (VLA) right here in New Mexico.

A new image released by the National Radio Astronomy Observatory (NRAO) shows the huge extent of a spiral galaxy's magnetic field. The galaxy, NGC 4217, is a star-forming, spiral galaxy, similar to Earths own Milky Way, 67 million light-years from Earth in the constellation Ursa Major. The galaxy is seen edge-on in a visible-light image from the Sloan Digital Sky Survey and Kitt Peak National Observatory, and the magnetic field lines, shown in green, are revealed by the VLA.

Most spiral galaxies consist of a flat, rotatingdiskcontainingstars,gas and dust, and a central concentration of stars known as thebulge. These are often surrounded by fainterhaloof stars, many of which reside inglobular clusters. Spiral galaxies are named after their spiral structure that is a feature of the disk. You can see the spiral structure when the galaxy is viewed face-on, but when viewed edge-on, you see just the disk that it resides in.

University of New Mexico graduate student Tim Braun and Professor Richard Rand from the Department of Physics and Astronomy are members of an international team of approximately 50 scientists who are part of a project called theContinuumHAlos inNearbyGalaxies anEVLASurvey (CHANG-ES), that is revealing new secrets about these magnetic fields.

Rand provided the optical image of the ionized hydrogen that was first published in 1996. It is seen in the reddish colors in the disk of the galaxy. That observation used exposures of more than three hours. The goal was to understand the occurrence and properties of ionized gas halos in edge-on galaxies in order to study vertical flows of gas in galaxies. Here, scientists are using the image mainly to show where star formation is currently occurring in the disk, although the absorption of light by interstellar dust grains in NGC 4271 limits scientists view somewhat.

The magnetic field lines extend as much as 22,500 light-years beyond the galaxy's disk. Scientists know that magnetic fields play an important role in many processes, such as star formation, within galaxies. However, it is not fully understood how such huge magnetic fields are generated and maintained. Magnetic fields area major component in the interstellar medium (ISM) of spiral, barred, irregular and dwarfgalaxies. They contribute significantly to the total pressure which balances the ISM against gravity. They may affect the gas flows in spiral arms, around bars and ingalaxyhalos

A leading explanation, called the dynamo theory, suggests that magnetic fields are generated by the motion of plasma within the galaxy's disk. Ideas about the cause of the kinds of large vertical extensions seen in this image are more speculative, and astronomers hope that further observations and more analysis will answer some of the outstanding questions.

The galactic dynamo theory is a way of explaining how large-scale, coherent magnetic fields can exist in galaxies, said Rand. They need to be continually regenerated because they are expected to be destroyed in a time much less than the age of a galaxy. The dynamo is a theory by which small-scale magnetic fields are turned into large-scale magnetic fields via motions in the galaxy. But the details are uncertain and more observations of the geometry and strength of magnetic fields in galaxies, like this one from the CHANG-ES project, are needed.

Understanding the magnetic field geometries of the CHANG-ES galaxies is just one goal of the project. Braun and Rands interest is in understanding the dynamical forces at play in galaxy halos and how they affect the motion of the gas that is ejected from the disk into the halo. Even for the magnetic field geometries, there is much more to do.

We are continuing to analyze the CHANG-ES data for magnetic field configurations in other galaxies, said Rand. Deeper observations of some of these galaxies could reveal more widespread magnetic geometries.

Last November, scientists as part of the CHANG-ES collaboration released an image of the Whale Galaxy, which reveals hair-like filaments of the galaxy's magnetic field protruding above and below the galaxy's disk.

TheNational Radio Astronomy Observatory is a facility of the National Science Foundation, operated under cooperative agreement by Associated Universities, Inc.

IMAGE CREDIT: Composite image by Yelena Stein of the Centre de Donnes astronomiques de Strasbourg (CDS) with the support of Jayanne English (University of Manitoba). VLA radio data from Yelena Stein and Ralf-Juergen Dettmar (Ruhr University Bochum). The observations are part of the project Continuum HAlos in Nearby Galaxies an EVLA Survey (CHANG-ES) led by Judith Irwin (Queens University, Canada). The optical data are from theSloan Digital Sky Survey. The ionized hydrogen data (red) are from the 0.9m telescope of the Kitt Peak National Observatory, collected by Richard J. Rand of The University of New Mexico. The software code for tracing the magnetic field lines was adapted by Y. Stein from Linear Integral Convolution code provided by Arpad Miskolczi of Ruhr University Bochum.

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UNM astronomers on team revealing the magnetic field of a spiral galaxy - UNM Newsroom

Asteroid discovered by UH telescope will make close pass Monday – UH System Current News

Asteroid 2020 OO1 detected near Earth, projected to make close approach

An asteroid discovered on July 20 by the University of Hawaiis Pan-STARRS1 telescope atop Haleakal will make a close pass of Earth on Monday, July 27. At its closest point, the asteroid will be only about 1.7 times the distance of the Moon. A short time after the July 20 discovery, the Center for Near-Earth Object (NEO) Studies at NASA issued a notification that it would likely come close to Earth. Several telescopes around the world, including the Canada-France-Hawaii Telescope on Maunakea, assisted with rapid follow-up observations to verify the asteroids orbit and determine if it was possibly hazardous.

Pan-STARRS1 is the world leader in finding large Near-Earth Objects (NEO), and this recent discovery is the latest example of the fundamental role Hawaii astronomy plays in the nations planetary defense system.

The NEO has been given the temporary name 2020 OO1, and has a diameter of approximately 65 feet (20 meters)the length of about two school buses. It is similar in size to the asteroid that exploded in the atmosphere over Russia in 2013 that sent a shock wave that blew out the windows of 7,200 buildings across six Russian cities.

Finding these objects is the bread-and-butter work of Pan-STARRS, said UH Institute for Astronomy (IfA) Astronomer Richard Wainscoat, who leads the NEO project with STARRS. Our mission is to find potentially hazardous asteroids together with the larger telescopes on Maunakea, the LCO (Las Cumbres Observatory) global telescope network, and our ATLAS (Asteroid Terrestrial-impact Last Alert System) project.

After Pan-STARRS identifies an object that might be passing very close, telescopes on Maunakea and elsewhere will stop what they are working on and track the object to determine if it is a possible threat to Earth. In this case, with all of the additional observations, including some taken by Hawaii high school students, astronomers have pinned down the orbit of 2020 OO1. The object has a tiny probability of hitting Earth in 2087. Astronomers will continue to observe this object as it approaches in order to refine their projections. These new observations will likely rule out future impacts.

The search for NEOs is funded by NASAs Planetary Defense Coordination Office through its Near-Earth Object Observations Program.

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Asteroid discovered by UH telescope will make close pass Monday - UH System Current News

The astronomical rise of esports – The Chronicle – Duke Chronicle

If youre bored during quarantine and looking for a fun, popular and lucrative way to pass the time, consider putting down that baking pan or pausing that Netflix show and picking up a controller to join the world of esports, a hot trend in the media and entertainment industry. Esports is a competitive video game sport that has grown to incorporate organized tournaments with professional players. Before the COVID-19 pandemic, these tournaments were almost always in-person events, complete with live audiences and referees who monitored potential cheating.

If this is your first time hearing about esports, youre behind the curve esports is one of the fastest growing industries in the world.Last year, the esports industry had an estimated audience of 453 million, up from 293 million in 2016. By 2021, that number is expected to reach 557 million. And its not just your stereotypical G Fuel-drinking, Doritos-loving high school guys pushing this growth: Universities across the nation have begun investing in this industry. According to the National Association of Collegiate Esports, more than 170 U.S. colleges have varsity esports programs and are offering around $16 million per year in scholarships. College esports tournaments have attracted over 1,350 schools and 40,000 players.

Even the most traditional Wall Street bankers are taking notice of this industrys potential to make big money. Most esport viewers are in their teens or early twenties, a much-coveted demographic for advertisers, and 43% of esports fans have an annual household income of $75,000. For brands who want to acquire new, young, high-spending customers, esports is especially attractive. Louis Vuitton, for example, is collaborating with video game developer Riot Games to design virtual items in League of Legends (such as prestige skins) that players can buy using real money. The fashion brand also spent 900 hours creating an extravagant custom trophy case that combines Louis Vuittons bougie flair with League of Legends medieval style. Meanwhile, some companies have profited from esports without even trying. In 2018, professional gamer Ninja crashed the website of MeUndies just by mentioning the underwear brand on a livestream.

Why has esports experienced this meteoric rise in popularity and significance? From a social standpoint, esports is far more inclusive than other sports. Men and women of nearly all ages and from various social groups and demographics can play on the same teams and easy translation in the virtual format tears down the language barrier. Unlike in real sports, where genetics may greatly affect your potential to succeed, in esports, anyone with enough practice can become a competent gamer and everyone has the potential to compete with the best.

From a technological standpoint, video games with increasingly life-like visuals have enhanced the viewing experience. Games now frequently run on a smooth 60 frames per second with 4K resolution, resulting in extremely realistic animations and an immersive experience. The rise of esports can also be traced to the rise of video games among youth. According to Pew Research, 90% of teens aged 13-17 played video games in 2018. The percentage is 97% among boys of that age. With a high number of youth playing games, its not hard to imagine that a few would get interested in esports and start the trend among their peers.

The viewership of esports will only grow, especially as famous names in other industries, such as Jennifer Lopez and Travis Scott, associate themselves with leading esports tournaments. The growth of advertising in esports means that brands will now interface directly with previously hard-to-reach audiences, generating previously unthinkable ways to advertise and making space for unlimited creative potential. So, if you want to curb your bread-making addiction during quarantine and spend this extra time getting ahead of the game (pun absolutely intended), consider esports.

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The astronomical rise of esports - The Chronicle - Duke Chronicle

Shining stars: The Astronomy Photographer of the Year shortlist – New Atlas

The Insight Investment Astronomy Photographer of the Year is one of the worlds top astrophotography competitions, and the 2020 shortlist offers a sublime selection of this years best entries, from some mind-bending close-ups of the suns surface to a series of magnificent Milky Way skyscapes.

The contest is run by the Royal Observatory Greenwich, an iconic scientific institution founded nearly 400 years ago. There are eight key categories in the contest, spanning a broad spectrum of astrophotography styles, from skyscapes incorporating land perspectives, to more focused categories looking at galaxies and aurorae.

BEN BUSH

As with previous years, the contest illustrates the incredible skill and determination these photographers display to create these images. UK photographer Ben Bushs shot of an aurora over Icelands famous Vestrahorn is a great example. To get the perfect shot of the aurora reflecting over the water, Bush waded out into the freezing North Atlantic ocean in the middle of night.

Mathew Browne

Other shortlisted images highlight the patience and timing needed to compose the ideal frame. Matthew Browns shot of the Moon passing behind Londons Shard skyscraper is an example of a fleeting moment in time that took the photographer days to catch.

Kirsty Paton

The winning photographs will be revealed later in the year, sharing 10,000 in prize money.

Take a look through our gallery at more shortlisted images from this years contest.

Source: RMG

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Shining stars: The Astronomy Photographer of the Year shortlist - New Atlas

How this e-learning platform on Astronomy can answer all your questions about the universe – EdexLive

Everybody is curious to know about the universe but in the process of knowing it, we also learn and develop some superstitious beliefs. Shweta Kulkarni was also curious to know more about the universe but she channelled her interest in the right direction. That's how she was able to start the digital platform AstronEra. This 24-year-old, who is a Royal Astronomical Society fellow, tells us about her interest in the subject, "I was only 16 years old when my parents bought me my first telescope. I would show my friends the stars and other interesting things in the sky. They were really impressed with me. Gradually, I read more and learnt more about astronomythrough various platforms. When I was 18, I co-founded a non-profit organisation called Astron-SHK."

While educating youngsters about astronomy, she met several experts like Dr Govind Swarup, Professor Jayanth Narlikar and many others. That's when she got the idea to create astronomy-based videos, which eventually won her international fame. Shweta explains, "I wrote to the Department of Science and Technology about the lack of astronomical videos available for learners and our interest to create some of them. They gave us a grant of `2.5 lakh and we were able to produce five videos especially for the beginners in astronomy. We were invited to the International Astronomical Youth Camp held in the UK and were surprised to see that most of the people had already watched our videos. What they liked about them was the contribution of Indian scientists in the field of Astronomy."

With this newfound popularity for her videos, she decided to start AstronEra, an e-learning platform, in 2018. "Everybody has the right to learn about this subject and develop a scientific temperament, and AstronEra facilitates the same. This digital platform, incubated at IIMB'sNSRCEL, provides a wide range of astronomical courses for people of all agegroups." Currently, Shweta who is pursuing a BSc in Astronomy with Honours from theUniversity of Central Lancashire through distance learning, builds the content for these courses with the help of mentors and her friends who are also experts in the field. She explains, "There are different courses including space exploration, Hubble space telescope, a guide to buy a telescope, exploring the solar system, astronomy without a telescope and so on. As many students have shown an interest in studying Astronomy during the lockdown, we are offering most of these courses at half price. Over 2,000 students have taken up these courses so far."

Shweta also goes to government schools or schools in tribal regions to create awareness about the universe and various eclipses so that they don't follow superstitious beliefs. A few months ago, Shweta's team visited around 500 tribal schools in Maharashtra with a telescope and helped students observe the Moon. "They were surprised, happy and found it amazing. What more can I ask for? We also gave them two of our online courses for free which were translated to Marathi and Hindi. All I dream is to spread the knowledge of Astronomy and bring that interest for this subject among the youngsters," she concludes.

To know more about their interesting courses, you can checkastronera.org

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How this e-learning platform on Astronomy can answer all your questions about the universe - EdexLive

The wheel with 12 spokes: Astronomy in ancient India – The New Indian Express

There are very many references to the Sun, Moon, stars, planets, meteors, etc., in Vedic literature before 1500 BCE. The Sun is the Lord of the universe, and the Moon shines by the Suns light. The Earth is described as a sphere.

Even casual observations of the sky would reveal that there are three clear time-markers in the sky, namely, a day, a lunar month and a year. All the major civilisations tried to understand the correlations among these time units. A verse in Rigveda says: The wheel (of time) formed with 12 spokes, revolves round the heavens, without wearing out. O Agni, on it are 720 sons (that is, days and nights).

So, a year has 12 months and 360 days. Later in Taittireeya Samhitaa, there is a clear mention of a solar year of 365 days. The names of the 12 months are given in this Samhitaa as: Madhu, Maadhava, Shukra, Shuci, Nabhas, Nabhasya, Isha, Urjaa, Sahas, Sahasya, Tapas and Tapasya. Now a lunar month is nearly 29.5 days, and 12 lunar months make 354 days. To align the lunar months and the solar year, there would be an extra intercalary month or adhika maasa called samsarpa in some years.

In the Rigveda, it is stated that God Varuna charted a broad path for the Sun in the sky. This obviously refers to the ecliptic, which is the path of the apparent motion of the Sun around the Earth in the sky, in the stellar background. It is inclined to the celestial equator, which is a large circle in the sky in the plane of Earths equator. This is depicted in the picture above.

Here S1, S3 are the equinoxes, S2 is the summer solstice, and S4 is the winter solstice. Vedic literature describes the apparent half-yearly northern (Uttaraayana; from S4 to S2), and southern (Dakshinaayana; from S2 to S4) motions of the Sun, and equinoxes in Taittireeya Samhitaa, Aitareya Braahmana and other texts.

The Moons sidereal period is nearly 27 days, and its path is only slightly inclined to the ecliptic. Then it is convenient to divide the ecliptic into 27 equal parts called nakshatras. This concept is essentially Indian, and the names of the 27 nakshatras, Ashvini, Bharani, ... Revati are also listed in the Taittireeya Samhitaa. The Samhitaa also refers to a five-year yuga cycle, wherein the Sun and the Moon return together at the same position in the sky after five years. All in all, there are rudiments of a calendar with 12 months in a year, inclusion of intercalary months appropriately, and 27 nakshatras as markers of the Moons movement. But it is not formulated mathematically and there are no clear rules.

It is in Vedaanga Jyotisha, ascribed to sage Lagadha, that we have a quantitative calendrical system, with a five-year yuga. One of the verses in it says: When the Sun and Moon occupy the same region of the zodiac together with the asterism of Vaasava (Shravishthaa), at that time begins the yuga, the synodic month of Maagha, the solar month called Tapas, the bright fortnight (of Maagha) and their northward course (Uttaraayana). So, winter solstice is at the beginning of Shravishthaa (Delfini) constellation. This corresponds to some time between 1370 BCE and 1150 BCE, though the text could have been composed a little later.

In the Vedaanga Jyotisha calendar, one has a yuga with five years, 60 solar months, 62 lunar months and 1,830 civil days. There are two adhikamaasas in five years. The concept of a tithi, which is 1/30 of a lunar month, is mentioned, perhaps for the first time. Vedaanga Jyotisha is the first text in India to give simple arithmetical algorithms in calendrical astronomy for finding tithi, nakshatra, the positions of the Sun and the Moon in the sky, and so on. There is nothing on planetary motion.

Compared to the actual value of 365.2564 days for a sidereal year, the Vedaanga Jyotisha value is 366 days. It has been suggested that this was for ease of calculations, with corrections introduced appropriately.

The Vedaanga Jyotisha gives a formula for the duration of day time (sunrise to sunset), according to which it is 12, 15 and 18 muhoortas, when the Sun is at the winter solstice, equinox and summer solstice respectively (one muhoorta is 48 minutes). The formula is reasonably correct for a latitude around 28.

The Kaatyaayana Sulbasutra (composed around 5th century BCE) describes the determination of the east and west directions from the shadows of a gnomon. Data for the annual and diurnal variations of a gnomon-shadow, given in Arthashastra and many Jaina and Buddhist texts around 300 BCE, seem to be based on observations. Recent research indicates that an eclipse cycle of nearly 18 years was in vogue even before the Vedaanga Jyotisha.

There is a long gap between 300 BCE and Aryabhateeya, the first extant text on full-fledged mathematical astronomy in India, composed in 499 CE. However, there were 18 siddhaantas earlier, five of which were summarised in Varaahamihiras Pancasiddhaantikaa composed around 520 CE. Exciting research on pre-Aryabhatan astronomy is going on.

M S Sriram

Theoretical Physicist & President,Prof. K.V. Sarma Research Foundation

(This is the fourth article in the series on Indias contributions to science and technology)

(sriram.physics@gmail.com)

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The wheel with 12 spokes: Astronomy in ancient India - The New Indian Express

Universe is 13.77 Billion Years Old, Astronomers Say | Astronomy – Sci-News.com

Astronomers using NSFs Atacama Cosmology Telescope (ACT) have taken a fresh look at the Cosmic Microwave Background (CMB), the oldest light in our Universe. Their new observations suggest that the Universe is 13.77 billion years old, give or take 40 million years. This estimate matches the one provided by the Standard Model of the Universe and measurements of the same light made by ESAs Planck satellite.

This new picture of the Cosmic Microwave Background, the oldest light in the Universe, was taken by the Atacama Cosmology Telescope. This covers a swath of the sky 50 times as wide as the Moon, representing a region of space 20 billion light-years across. The light, emitted just 380,000 years after the Big Bang, varies in polarization (represented here by redder or bluer colors). Image credit: ACT Collaboration.

The Standard Model, the one behind Jim Peebles Nobel Prize, comes through with flying colors, said Professor Lyman Page, an astrophysicist at Princeton University who was the ACTs principal investigator from 2004 to 2014.

This adds a fresh twist to an ongoing debate in the astrophysics community, said Dr. Simone Aiola, a researcher at Flatiron Institute and Princeton University.

In 2019, astronomers measuring the movements of galaxies calculated that the Universe is hundreds of millions of years younger than the Planck team predicted. That discrepancy suggested that a new model for the Universe might be needed and sparked concerns that one of the sets of measurements might be incorrect.

Now weve come up with an answer where Planck and ACT agree. It speaks to the fact that these difficult measurements are reliable, Dr. Aiola said.

The age of the Universe also reveals how fast the cosmos is expanding, a number quantified by the Hubble constant.

The ACT measurements suggest a Hubble constant of 67.6 km per second per megaparsec (km/s/Mpc).

This result agrees almost exactly with the previous estimate of 67.4 km/s/Mpc by the Planck satellite team, but its slower than the 74 km/s/Mpc inferred from the measurements of galaxies.

We dont know if the tension is due to systematic effects or to something new that we have not figured out. Cosmology is as exciting as ever, Professor Page said.

I didnt have a particular preference for any specific value it was going to be interesting one way or another, said Dr. Steve Choi, a scientist at Cornell University and Princeton University.

We find an expansion rate that is right on the estimate by the Planck satellite team. This gives us more confidence in measurements of the Universes oldest light.

The close agreement between the ACT and Planck results and the Standard Cosmological Model is bittersweet, Dr. Aiola said.

Its good to know that our model right now is robust, but it would have been nice to see a hint of something new.

Still, the disagreement with the 2019 study of the motions of galaxies maintains the possibility that unknown physics may be at play.

The Planck satellite measured the same light, but by measuring its polarization in higher fidelity, the new picture from ACT reveals more of the oldest patterns weve ever seen, said ACT principal investigator Professor Suzanne Staggs, of Princeton University.

The findings were published in a series of papers on the arXiv.org preprint server.

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Simone Aiola et al. 2020. The Atacama Cosmology Telescope: DR4 Maps and Cosmological Parameters. arXiv: 2007.07288

Steve K. Choi et al. 2020. The Atacama Cosmology Telescope: A Measurement of the Cosmic Microwave Background Power Spectra at 98 and 150 GHz. arXiv: 2007.07289

Sigurd Naess et al. 2020. The Atacama Cosmology Telescope: arcminute-resolution maps of 18,000 square degrees of the microwave sky from ACT 2008-2018 data combined with Planck. arXiv: 2007.07290

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Universe is 13.77 Billion Years Old, Astronomers Say | Astronomy - Sci-News.com

Vanderbilt, The Ohio State University are joint Founding Members of satellite mission Twinkle to find potentially habitable worlds around nearby stars…

Astronomers are preparing to further study the atmospheres of planets discovered through NASAs Transiting Exoplanet Survey Satellite (TESS) mission, to identify the most promising exoplanetsplanets in solar systems beyond our own for habitability and signs of life.

Set to launch in late 2023, Twinkle is a space mission that will deliver unprecedented data via satellite telescope to astronomers about the elemental composition of exoplanet atmospheres. Vanderbilt and The Ohio State University have become Founding Members of the mission and will play a leading role in shaping the missions directives, targets, and survey operations.

We already have a decent estimate of the number of Earth-like planets with similar size, mass and bulk composition in our galaxy, but what we dont yet know is how common atmospheres like ours are on these planets, said Keivan Stassun, Stevenson Professor of Physics and Astronomy, who will lead Vanderbilts Team Twinkle. The Twinkle mission can bring answers to this burning question. The measurements that we will take will help us identify planets with atmospheres, and of those, which are breathable and livable.

Finding Earth-like planets orbiting Sun-like stars with oxygen-rich atmospheres and an ozone layer in the upper atmosphere to protect life from being mutated by UV rays, like what we have on this planet, is no small feat. As a co-investigator of the TESS mission, Stassun has spent the last eight years developing, designing, launching and running the program. Following several successful discoveries of potentially habitable planets during the TESS mission, Stassun and his team are cautiously optimistic about the opportunity presented by Twinkle.

Stassun, together with the Twinkles other Founding Members, The Ohio State Universitys Scott Gaudi, Thomas Jefferson Professor for Discovery and Space Exploration and Ji Wang, assistant professor of astronomy, are assembling a hit list of target planets to study until the satellites launch. Once the satellite is in its sun-synchronous, low-Earth polar orbit, the team will collect and calibrate data, sitting at the computer screen with bated breath for the first signs of breathable atmospheres. The full data analysis will take a few years to process and will identify exciting opportunities for further science during the missions extended seven-year lifetime.

Twinkle is nimble, so we will be able to observe many candidates with multiple visits to the same target, said Wang. We also have a very competitive team here at Ohio State that can leverage NASAs James Webb Space Telescope mission to focus on a handful of the most promising targets identified for biosignature detection. Finding biosignatures on exoplanets represents one of our best chances of finding signs of life elsewhere.

With a core group of faculty, postdoctoral scholars, graduate students and undergraduates all engaged in cutting-edge research, the departments of astronomy at Ohio State and Vanderbilt have worked together to establish themselves as leaders in the study of exoplanets planets orbiting other stars and the search for life on these worlds, said Gaudi. As founding members of the Twinkle mission with our colleagues at Vanderbilt, we will further cement our departments as centers for the study and characterization of exoplanets.

Stassun, also director of the Frist Center for Autism and Innovation, is building his team that will be working on data visualization and analysis to include neurodiverse students through the Centers autism internship program. I have been convinced that applying the full diversity of the human mind is how were going to make progress and solve these exciting open questions, he commented.

In addition to atmospheric research of exoplanets, Twinkles broad-wavelength spectroscopic capabilities will also enable astronomers to study the surfaces of asteroids and nuclei of comets in our solar system. Beyond these core science cases, scientists can use Twinkle to monitor stellar activity and variability, observe protoplanetary disks around stars in various stages of planet formation, study brown dwarfs and shed new light on the planets and moons in our solar system.

Twinkle is the inaugural mission of Blue Skies Space Ltd., a company incorporated in England and Wales. Blue Skies Space was co-founded by Marcell Tessenyi, Giovanna Tinetti and Jonathan Tennyson, all academics working at University College London, to deliver independent satellites that address the global scientific communitys need for high-quality data from space.

Vanderbilts participation in the Twinkle Mission is funded through the Vanderbilt Initiative in Data-intensive Astrophysics (VIDA). Blue Skies Space is funded by a combination of private and public sources including the UK Space Agency (UKSA) and European Space Agency (ESA) which support the development of this innovative new model for delivering space science missions. The Ohio State Universitys participation is funded through the Universitys Thomas Jefferson Chair for Discovery and Space Exploration endowment.

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Vanderbilt, The Ohio State University are joint Founding Members of satellite mission Twinkle to find potentially habitable worlds around nearby stars...

Pastor-astronomer: Recent solar events are gifts of awe – Suburbanite

"The heavens declare the glory"

NORTH CANTON July has been an auspicious month for stargazers like the Rev. David Ross, a lifelong of student of astronomy.

Hes been watching the Comet NEOWISE, which can be seen unaided in Northeast Ohio, just prior to sunrise. It will not return for 6,800 years.

On Sunday, the full moon, Jupiter and Saturn will align. On July 29, the Southern Delta Aquariids meteor shower will occur in the northeast skies.

"Theres always something interesting going on up there," he said.

Ross, a retired minister who co-pastors Simpson United Methodist Church in Plain Township with his wife, Barb, said the stars are a gift of Gods creation to provide humans with a sense of awe and wonder.

"I grew up in the 60s when the space program was all the rage," he said. "That just kind of stoked my interest over the years. Ive been able to enjoy building a telescope and taking pictures of comets, like Hale-Bopp."

In past years, Ross has done presentations on the Bethlehem Star.

"Certainly the Gospel mentions the Star of Bethlehem," he said. "Over the years, Ive come to appreciate, in terms of faith, the wonder of the world around us."

Ross cites theologians such as William Brown, who have noted that the Bibles "wisdom" literature - Proverbs, Ecclesiastes, Job and others - contributes to the formation of character through extolling natures wonders.

"If youre able to open yourself up through the gift of creation and the strange things which humble us, thats an important element for building character," he said. "The fear of the Lord is the beginning of wisdom."

Ross recalls being in awe during the last solar eclipse, which he saw in Nashville.

"Its an uncanny feeling to see that. To think that people in earlier times and ages must have wondered what this is all about," he said. "In 2024, its going to be the full megillah. The line goes through Wooster and Cleveland, so we dont have to travel very far."

He noted that ancient people viewed comets as a bad omen. Prior to Comet NEOWISE, there were two others in March and April.

"I think the Lords trying to tell us something," he laughed. "Of course, hes always trying to tell us something. If it takes a comet to do that..."

Ross said he thinks the current pushback against science is a result of institutions being buffeted by scandals.

"So many institutions and authority figures have been undermined," he said. "Everybody seems to think they can go their own way and be their own authority. With the virus, I would have thought the science behind how we stay well would have been one the place where we put some trust.

"In church we pray for people who are sick, but hope the doctors do their best. Some challenge is appropriate, but we see what can happen if everything becomes a matter of opinion. It happened in Bible times when the prophets said, `Everyone went their own way. Its a recipe for chaos."

Ross said his favorite Scripture regarding astronomy is Psalm 19:

"The heavens declare the glory of God."

"C.S. Lewis said he thought those lines were some of the most beautiful written in the English language," he said. "Hes someone who had a real sense of how the stars and sky through the ages have spoken to religious people and nonreligious people."

Lewis "Narnia" series, he noted, makes use of stars and planets in their plots.

In 2014, the Star of Bethlehem Conference observed its 400th anniversary at University of Groningen in the Netherlands. The group was founded by Johannes Kepler, who wrote a theory contending there was an alignment of the planets.

"For me, its less the scientific search than the wonder," Ross said. "I got interested in Bethlehem Star from `Its a Wonderful Life."

The film opens on an image of a group of galaxies known as Stephans Quintet.

"(Director) Frank Capra had a lifelong interest in astronomy," Ross said. "He studied at what became Cal Tech. At the time, those galaxies were the definition of things to wonder about. Its key element of the storyline."

Last year, Ross spoke at festival in Seneca Falls, N.Y., which honors the film.

"Its not until George (Bailey) changes his perspective, its after that hes able to see the stars," Ross said. "Its after he comes back from the bridge that hes able to see the stars again."

Ross urges people to visit Stark County Wilderness Center Education Director Robin Gills Facebook page, which features information on stargazing.

"It doesnt take a group or gathering to enjoy astronomy," he said.

Reach Charita at 330-580-8313 or charita.goshay@cantonrep.com

On Twitter: @cgoshayREP

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Pastor-astronomer: Recent solar events are gifts of awe - Suburbanite

Astronomy: Probe, rover, helicopter to head to Mars this month – The Columbus Dispatch

July is a busy month for missions to Mars. Earth and Mars are now close enough in their orbits that a launch window is open. Three missions to Mars, one from NASA, one from China, and one from the United Arab Emirates, are to blast off soon.

The UAE space probe called Hope is to go first, on Monday, after bad weather scuttled last weeks launch dates. The probe is to be propelled on top of a Japanese H-IIA rocket built by Mitsubishi Heavy Industries. The goal is to put a weather satellite in orbit around Mars to study its atmosphere in hopes of finding the reason for the atmospheres large changes over the past millennia. Long ago, Mars could sustain liquid water on its surface. Today, it has a thin, dry atmosphere. The UAE has partnered with several universities in the U.S. to design a multi-wavelength spectrometer to study the seasonal weather cycles over several years.

China has divulged little about its plan to send up a rover and an orbiter in late July or early August in a mission named Tianwen, or Questions for Heaven.

Also in late July, NASA is to launch a new rover called Perseverance using an Atlas rocket. This rover will be the size of a small car, much larger than the little rovers sent many years ago and similar in size to the Curiosity rover that landed in 2012. Whats new is that Perseverance will have a drill that can cut into a rock to remove a core sample about the size of a pen. It will take the rock samples to a drop-off spot for possible retrieval by a future mission to Mars. A campaign has been started jointly by NASA and the European Space Agency to plan a mission to bring those samples back to Earth for analysis.

Now for the really cool part. Along with Perseverance, a small helicopter called Ingenuity, which has carbon-fiber blades and weighs about 4 pounds, will be sent to Mars. It will just be a technology demonstration, but if Ingenuity succeeds in flying, it will be the first drone to fly on another planet. The Martian air is thin. so the blades need to be long about 4 feet and will spin about eight times faster than those on a helicopter on Earth.

One problem is that, due to the time lag of several minutes in communications from Earth to Mars, Ingenuity must fly itself, using an onboard computer. When flying, it wont be controlled by a human but will rely on instructions programmed into its computer. Ingenuity has a wireless connection to Perseverance, which in turn communicates with an orbiting satellite that gets radio commands from Earth. Ingenuity also has a camera, enabling it to take overhead pictures that can be relayed back to us.

The goal of these missions is to find out whether microbial life once flourished on Mars. Clear evidence of past life on Mars has eluded us.

Ken Hicks is a professor of physics and astronomy at Ohio University in Athens.

hicks@ohio.edu

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Astronomy: Probe, rover, helicopter to head to Mars this month - The Columbus Dispatch

China launches robotic mission to orbit, land, and drive on Mars – Astronomy Now Online

A Long March 5 rocket takes off Thursday from the Wenchang Space Launch Center on Hainan Island with the Tianwen 1 Mars mission. Credit: Xinhua

A heavy-lift Long March 5 rocket propelled Chinas first Mars landing mission toward the red planet on Thursday after launching from a seaside spaceport on Hainan Island, the second of three international Mars probes expected to depart planet Earth this month.

Kicking off a nearly seven-month journey, Chinas Tianwen 1 spacecraft lifted off from the Wenchang Space Launch Centre in southern Chinas Hainan province at 0441 GMT (12:41 p.m. Beijing time) on top of a Long March 5 rocket, the heaviest launcher in the countrys inventory.

A live video feed streamed by amateur spectators near the launch site showed the Long March 5 rocket climbing away from the Wenchang spaceport. Ten rocket engines fueled by kerosene and liquid hydrogen powered the 57-meter tall Long March 5 into a sunny midday sky, and the rocket quickly receded from view in the unofficial online video feed.

Chinese state media did not broadcast the mission live or publicize the exact launch time in advance, but airspace and maritime notices warning pilots and sailors to steer clear of downrange drop zones suggested the Long March 5 was scheduled to lift off Thursday.

Chinese authorities lifted the news blackout on the launch once the 5-tonne Tianwen 1 spacecraft was injected onto a trajectory toward Mars by the Long March 5s second stage. The China National Space Administration confirmed the Long March 5 rocket placed Tianwen 1 on the proper course toward Mars about 36 minutes after launch.

The China Aerospace Science and Technology Corp., the government-owned prime contractor for Chinas space programme, declared the launch a success in a statement.

Tianwen 1 is scheduled to arrive at Mars next February after a seven-month voyage. If successful, the mission will be Chinas first probe to enter orbit around another planet.

Two-to-three months later, the Tianwen 1 orbiter will release a lander to enter the Martian atmosphere and aim for a controlled touchdown in Utopia Planitia, a broad plain in Marss northern hemisphere. Once on the surface, the lander will lower a ramp and a 240-kilogramme rover will drive onto the surface.

If China pulls off those feats according to plan, they will make China the third country to perform a soft landing on Mars after the Soviet Union and the United States and the second country to drive a robotic rover on the Red Planet.

NASA has landed the only successful rovers on Mars to date.

The seemingly flawless launch Thursday by the Long March 5 rocket gives Chinas most powerful launcher an 80 percent success record after five flights. The Long March 5 failed on its second test flight in 2017, but has now logged three consecutive successes.

Tianwen 1 is Chinas next leap in Solar System exploration after a series of progressively complex robotic expeditions to the moon.

Most recently, China has landed two rovers on the Moon, including the first to explore the surface of the lunar far side. The next Chinese lunar mission, named Change 5, is scheduled for launch on a Long March 5 rocket late this year on a mission to return samples from the Moon.

China officially started development of the Mars mission in 2016.

It will be the countrys second attempt to reach Mars with a robotic probe, following the Yinghuo 1 orbiter, which was stranded in Earth orbit after launch as a piggyback payload on Russias failed Phobos-Grunt mission.

Benefiting from the engineering heritage of Chinas lunar exploration programme,the Chinese national strategy set Mars as the next target for planetary exploration, wrote Wan Weixing, chief scientist of Chinas Mars exploration programme, in a paper published this month by the science journal Nature Astronomy. Chinas first Mars mission is named Tianwen 1, and aims to complete orbiting, landing and roving in one mission.

Wan died in May after a long illness.

Chinese officials announced the Tianwen name for the countrys planetary missions in April. The name Tianwen comes from the work of ancient Chinese poet Qu Yuan, meaning quest for heavenly truth, according to the China National Space Administration, or CNSA, the countrys space agency.

The countrys first Martian probe will conduct scientific investigations about the Martian soil, geological structure, environment, atmosphere, as well as water, CNSA said in a statement.

After reaching Mars in February, the Tianwen 1 spacecraft will initially enter a long-period capture orbit around the Red Planet. The orbiter will eventually settle in a loop around Mars ranging between 265 kilometres and nearly 12,000 kilometres over the Martian poles.

As soon as next April, the lander and rover modules will detach from the orbiter to begin a descent through the Martian atmosphere. Radar soundings from orbit have indicated the presence of a reservoir of ice containing as much water as Lake Superior, the largest of the Great Lakes, in the Utopia Planitia region targeted by Tianwen 1s lander.

The Tianwen 1 orbiter is designed to operate for at least one Martian year, or about two years on Earth. The solar-powered rover, fitted with six wheels for mobility, has a life expectancy of at least 90 days, Chinese officials said.

Chinese scientists say the Tianwen 1 mission will perform a global survey of Mars, measuring soil and rock composition, searching for signs of buried water ice, and studying the Martian magnetosphere and atmosphere. The orbiter and rover will also observe Martian weather and probe Marss internal structure.

The orbiters seven instruments include a:

The Tianwen 1 rover is cocooned inside a heat shield for a fiery descent to the Martian surface. After releasing from the orbiter mothership, the lander will enter the red planets atmosphere, deploy a parachute, then fire a braking rocket to slow down for landing.

Tianwen 1 is going to orbit, land and release a rover all on the very first try, and coordinate observations with an orbiter, Wan wrote in Nature Astronomy. No planetary missions have ever been implemented in this way. If successful, it would signify a major technical breakthrough.

Scientifically, Tianwen 1 is the most comprehensive mission to investigate the Martian morphology, geology, mineralogy, space environment, and soil and water-ice distribution.

The rovers six science payloads include a:

The rovers ground-penetrating radar would be one of the first science instruments of its kind to reach the surface of Mars. NASAs Perseverance rover carries a comparable instrument to scan subsurface layers of the Martian crust in search of water ice deposits.

Tianwen 1 is a Chinese-led project, but scientists and support teams from several countries have agreed to provide assistance on the mission.

Scientists from theInstitut de Recherche en Astrophysique et Plantologie, or IRAP, in France contributed to a Laser-Induced Breakdown Spectroscopy instrument on the Tianwen 1 rover.

French scientists, with support from the French space agency CNES, provided guidance to their Chinese counterparts on the spectroscopy technique, which uses a laser to zap a pinhead-size portion of a rock, and a spectrometer to analyze the light given off by plasma generated by the lasers interaction with the rocks surface.

The technique allows an instrument to determine the chemical make-up of rocks on Mars.

The discussions between French and Chinese scientists were intended to maximize the quality of the data produced by the Tianwen 1 rover, according to Agnes Cousin, a planetary scientist at IRAP who worked with Chinese researchers developing the rovers instruments.

French scientists from the same research institute helped develop the ChemCam instrument on NASAs Curiosity rover and the SuperCam payload set for launch 30 July on NASAs Perseverance Mars rover. ChemCam and SuperCam use the same Laser-Induced Breakdown Spectroscopy technique as the Tianwen 1 rover.

Researchers from France provided a norite calibration target to fly on the Tianwen 1 rover. Its similar to a unit on NASAs Curiosity rover used to calibrate ChemCams measurements by turning the instrument on a target like the rock norite with a known composition.

The SuperCam instrument on NASAs Perseverance rover will us a different type rock as a calibration target, but Cousin said scientists at her lab in France will still be able to cross-calibrate measurements from Curiosity, Perseverance, and the Tianwen 1 rover.

Scientists from the Space Research Institute at the Austrian Academy of Sciences assisted in the development of the magnetometer on the Tianwen 1 orbiter and helped calibrate the flight instrument.

Argentina is home to a Chinese-owned deep space tracking antenna that will be used to communicate with Tianwen 1 after launch. The European Space Agency has agreed to provide communications time for Tianwen 1 on its own worldwide network of deep space tracking stations, and help with the probes navigation on the journey to Mars.

The launch of the Tianwen 1 Mars mission Thursday occurred less than four days after the launch of the Hope Mars probe developed by the United Arab Emirates, and a week before NASAs Perseverance Mars rover is scheduled for blastoff.

The ever-changing positions of the planets only allow for missions to make a direct trip from Earth to Mars once every 26 months or so. The Mars launch window opened this year in mid-July and extends until mid-August.

While NASA and US scientists are aiding the UAEs Hope Mars orbiter, NASA has no such role on Chinas Tianwen 1 mission. NASAs Deep Space Network, which provides tracking and communications coverage for numerous US and international space probes, has not been called up to support Tianwen 1s voyage to Mars.

NASA Administrator Jim Bridenstine congratulated China on the successful launch Thursday.

With todays launch, China is on its way to join the community of international scientific explorers at Mars, Bridenstine tweeted. The United States, Europe, Russia, India, and soon the UAE will welcome you to Mars to embark on an exciting year of scientific discovery. Safe travels Tianwen-1!

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Follow Stephen Clark on Twitter: @StephenClark1.

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China launches robotic mission to orbit, land, and drive on Mars - Astronomy Now Online

Citizen scientists and astronomers find two strange, ancient brown dwarfs – Space.com

Citizen scientists recently helped direct astronomers to a pair of objects that straddle the line between planets and stars.

These newly-spotted substellar objects are brown dwarfs, which share many elements in common with stars. However, these gaseous bodies don't have enough mass to start nuclear fusion in their core, so they resemble planets more than stars.

The newfound brown dwarfs have very unusual compositions. They are the most planet-like brown dwarfs to be observed in the Milky Way's oldest populations of stars, NASA officials said in a statement. They also might help researchers learn more about planets outside the solar system.

Related: Best night sky events of July 2020 (stargazing maps)

The citizen scientists who spotted both objects were part of the ongoing NASA-funded Backyard Worlds: Planet 9 project. They were looking through spacecraft data from NASA's WISE and NEOWISE missions; both missions are chapters in the life of a single spacecraft called the Wide-field Infrared Survey Explorer.

And the objects that the collaboration recently found, now called WISE 1810 and WISE 0414, are weird.

When scientists studied them, they were surprised to see that these two brown dwarfs have very little iron compared to what's usually observed in brown dwarfs. This is a telltale sign that they are very old. The pair is estimated to be about 10 billion years old and to have a mass of about 75 times the mass of Jupiter, NASA said.

If these brown dwarfs formed with low levels of metal, so might ancient exoplanets. This could be a reason to search for old metal-poor exoplanets or alien worlds that orbit ancient metal-poor stars. Further research into this brown dwarf population could answer questions about how dependent the planet formation process is on the presence of metals.

A study accepted for publication in The Astrophysical Journal and uploaded to the preprint server arXiv.org details these findings. Its lead author is Adam Schneider from Arizona State Universitys School of Earth and Space Exploration in Tempe. Schneider first spotted WISE 1810 in 2016.

NASA representatives said Backyard Worlds: Planet 9 has contributed to more than 1,600 brown dwarf discoveries.

Follow Doris Elin Urrutia on Twitter @salazar_elin. Follow us on Twitter @Spacedotcom and on Facebook.

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Citizen scientists and astronomers find two strange, ancient brown dwarfs - Space.com

Worlds Best Nightscape Photos: 15 Shortlisted Images For Astronomy Photographer Of The Year 2020 – Forbes

The Red Lake of Stars: Years ago, before over-fishing, Little Redfish Lake was called as such due to ... [+] the vast numbers of salmon turning the lake a red colour. The red colouration is no longer seen because of salmon, but the colour of sunsets and airglow during the night still turn the waters a vibrant red. It is these beautiful warm echoes of red, combined with the mirror-like reflections of the Sawtooth Mountains in the distance and the alignment of the Milky Way with the mountains that make Little Redfish Lake one of the most spectacular places the photographer has ever shot at night. The photographer recalls that we were fortunate enough that night to have the lakeshore to ourselves, just three of us, and a rather excited dog who tried his best not to run into our tripods! We spent the sunset here, waiting for the stars to come out and the Milky Way core to rise, marvelling at the red colour of the water.

Earlier this week I posted a selection of my favorites from a long list of shortlisted images from the newly-announced Insight Investment Astronomy Photographer of the Year2020 from the Royal Observatory Greenwich, London.

I short-changed you. Although I tried my best to select the most intriguing and impressive images from each of the nine categories, there were just so many beautiful images that show-off my favorite night sky sights of allthe Milky Way and the aurorathat it deserves a second visit.

Besides, although astrophotography is growing as a hobby as cameras improve, that is a very wide category and includes many technical deep-sky close-ups using telescopes. For me, its all about nightscapes and astro-landscape photography; photos that showcase the night sky.

Since its now Milky Way-spotting season across the world (look to the south after midnight from a dark sky destination and youll see our galaxy arcing across the sky), here are all of the shortlisted images from the eye-catching Skyscapes category ... along with a sprinkling of other Milky Way and aurorae images from other categories.

Enjoy the celestial show!

Galactic Portal: On the photographers trip to Australia, he travelled to the coastal town of Kiama, ... [+] where he captured his first Milky Way image of the year his first Milky Way image taken from the Southern Hemisphere. Once the sun set, the photographer made his way into the cave and waited for a few hours for the core of the Milky Way to appear. Being unfamiliar with the southern sky, the photographer was surprised to also see Jupiter appear soon after.

Beyond the Fog: the photographer had to wait, drenched on a rickety bridge until the thick fog had ... [+] cleared. He was rewarded with noctilucent clouds in the sky, the outlines of which were reflected in the mirror of the calm river. The photographers patience paid off as he caught the last outline of the departing mesospheric storm.

Cold Night on the Yellowstone: In mid-March, shortly after the core of our galaxy is visible above ... [+] the horizon, it rises in the final hours of darkness before dawn. Shooting this panorama scene, while night-time fog hung low over riverside cottonwood trees and the distant mountains of the Absaroka Beartooth Wilderness glowed from the light of countless stars, the photographer felt that he was able to capture a connectedness between this world and the one above a hint of changing seasons, and a sense that Nature continues to provide countless wonders for all willing to stop and look.

The Cave of the Wild Horses: Located in the heart of the desert in Southern Utah, the Cave of the ... [+] Wild Horses, with its copious wildlife, petroglyphs, rock varnish, and framed view of the summer Milky Way in its entrance, makes for a fairy-tale place to take astrophotographs. This photograph is one of the most complicated that the photographer has taken to date due to the location of the cave and the number of foreground images taken. Getting to the cave involves a long hike through the desert, over sandstone plateaus, through brush and desert sand. Upon reaching the cave, the photographer decided that she wanted to take a large panorama in order to preserve the feeling of looking out of the cave to the sky beyond.

The Red Lake of Stars: Years ago, before over-fishing, Little Redfish Lake was called as such due to ... [+] the vast numbers of salmon turning the lake a red colour. The red colouration is no longer seen because of salmon, but the colour of sunsets and airglow during the night still turn the waters a vibrant red. It is these beautiful warm echoes of red, combined with the mirror-like reflections of the Sawtooth Mountains in the distance and the alignment of the Milky Way with the mountains that make Little Redfish Lake one of the most spectacular places the photographer has ever shot at night. The photographer recalls that we were fortunate enough that night to have the lakeshore to ourselves, just three of us, and a rather excited dog who tried his best not to run into our tripods! We spent the sunset here, waiting for the stars to come out and the Milky Way core to rise, marvelling at the red colour of the water.

Something Old, Something New: The incredible site of the old Lithgow Blast Furnace has been restored ... [+] as a heritage icon in the area reflecting on the past history of the beginnings of the iron and steel industries in Australia. With some prior planning, visiting at night provides the mesmerising opportunity to capture the Galactic Core in the Milky Way as it passes overhead.

Stargazing Giant: this image is the view of the Milky Way rising above the Moai at Ahu Akivi. Ahu ... [+] Akivi is a particularly sacred place in Easter Island in the Valparaso Region of Chile, looking out towards the South Pacific Ocean. The site has seven moai, all of equal shape and size, and is also known as a celestial observatory that was set up around the 16th century. The shot highlights the central bulge of the Milky Way, the constellation Scorpio, as well as the planets Jupiter and Saturn.

Meeting: After a long hike and a little bit of climbing to the top of the mountain, the photographer ... [+] was able to see the Milky Way. He only had five minutes time to take the panorama shot before the clouds moved. The photographer and his friend are pictured standing on the edge, looking out at the sky and over the city of Fssen in Germany.

Beautiful Persian Gulf Nights: On one of the many hiking trails along Iran's coastline, the ... [+] photographer discovered this incredible lookout. The scale of the vista encouraged the photographer to capture a 360 degree panoramic image of the entire sky using 60 15-second exposures. The movement of the clouds meant that the photographer had a short time to capture the Milky Way. The photographer is pictured, enjoying the wonderland he stumbled across.

Milky Way and Meteor at Porthgwarra: Porthgwarra is a sheltered fishing cove in the west of Cornwall ... [+] and the U-shape of the narrow cove is perfect for framing the Milky Way. There was likely to be a boat in the cove but the photographer was very fortunate to find it perfectly positioned in the centre of the old slipway. The photographer shot several non-tracked sky exposures from the same tripod position to capture the cliffs and horizon (as these were blurred in the tracked shot) and in one, she was lucky enough to capture a meteor, which she copied into the final image. This is one of the photographers favourite locations in Cornwall and it was a magnificent night under the stars.

Geysir Aurora: Close to the Spring and Autumn Equinox, the Earth's magnetic field aligns with the ... [+] incoming solar wind to create a better chance for aurora activity. The photographer had been waiting for signs of solar storm near the equinox date hoping that the Russell-McPherron effect would kick in. During the last weekend in September it seemed there would be favourable terrestrial and space weather conditions, so the photographer travelled with a friend to Iceland. They were not disappointed. The northern lights danced all weekend, with clear skies every night. This shot shows the famous Geysir of Iceland preparing to blow with the aurora behind it.

Stokksnes Aurora: This image captures the stunning Stokksnes looking to the Vestrahorn and the most ... [+] powerful and beautiful night of aurora the photographer had ever seen. He travelled 1250 miles to try and capture his dream. In order to get the shot, the photographer ended up knee-deep in the North Atlantic in -6 degrees Celsius. The challenge was to capture the reflections in the water, on the black sand beach, and also not to over-expose the aurora. The photographer describes this as a truly awe-inspiring experience and one he feels blessed to have witnessed and captured on camera.

Northern Dragon's Eye:The photographer loves to travel, especially exploring the north and chasing ... [+] the Northern Lights. Trying to capture how ordinary things can take magical forms under the lights, the photographer selected and lit this rocky outcrop and waited for the aurora to work its magic.

Hamny Lights: After two weeks of storm, clouds and snow in the Lofoten Islands, the sky finally ... [+] cleared up, providing perfect conditions for hunting the northern lights. The photographer waited patiently in their car for the light show to begin and on the first sign of the aurora borealis in the sky, he set up his camera at this famous overlook of the idyllic fishing village Hamny. The image is a manual exposure blend consisting of one base image for the sky and foreground plus a total of seven bracketed images to balance the highlights and shadows in the fishing village and water.

Kynance Cove under the Milky Way: This image is only the photographer's second attempt at shooting ... [+] the Milky Way. It shows our galaxy over Kynance Cove in Cornwall, a beautiful spot with dark skis. It was taken on a cold, but fabulous night under the stars. As it was July, the sky was very blue, with full darkness only for about an hour. The foreground was taken at dusk and the sky is a stack of 4 images of 25 seconds taken later when the Milky Way appeared, the sky and foreground blended together in post processing.

Wishing you clear skies and wide eyes.

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Worlds Best Nightscape Photos: 15 Shortlisted Images For Astronomy Photographer Of The Year 2020 - Forbes

Pastor-astronomer: Recent solar events are gifts of awe – Massillon Independent

"The heavens declare the glory"

NORTH CANTON July has been an auspicious month for stargazers like the Rev. David Ross, a lifelong of student of astronomy.

Hes been watching the Comet NEOWISE, which can be seen unaided in Northeast Ohio, just prior to sunrise. It will not return for 6,800 years.

On Sunday, the full moon, Jupiter and Saturn will align. On July 29, the Southern Delta Aquariids meteor shower will occur in the northeast skies.

"Theres always something interesting going on up there," he said.

Ross, a retired minister who co-pastors Simpson United Methodist Church in Plain Township with his wife, Barb, said the stars are a gift of Gods creation to provide humans with a sense of awe and wonder.

"I grew up in the 60s when the space program was all the rage," he said. "That just kind of stoked my interest over the years. Ive been able to enjoy building a telescope and taking pictures of comets, like Hale-Bopp."

In past years, Ross has done presentations on the Bethlehem Star.

"Certainly the Gospel mentions the Star of Bethlehem," he said. "Over the years, Ive come to appreciate, in terms of faith, the wonder of the world around us."

Ross cites theologians such as William Brown, who have noted that the Bibles "wisdom" literature - Proverbs, Ecclesiastes, Job and others - contributes to the formation of character through extolling natures wonders.

"If youre able to open yourself up through the gift of creation and the strange things which humble us, thats an important element for building character," he said. "The fear of the Lord is the beginning of wisdom."

Ross recalls being in awe during the last solar eclipse, which he saw in Nashville.

"Its an uncanny feeling to see that. To think that people in earlier times and ages must have wondered what this is all about," he said. "In 2024, its going to be the full megillah. The line goes through Wooster and Cleveland, so we dont have to travel very far."

He noted that ancient people viewed comets as a bad omen. Prior to Comet NEOWISE, there were two others in March and April.

"I think the Lords trying to tell us something," he laughed. "Of course, hes always trying to tell us something. If it takes a comet to do that..."

Ross said he thinks the current pushback against science is a result of institutions being buffeted by scandals.

"So many institutions and authority figures have been undermined," he said. "Everybody seems to think they can go their own way and be their own authority. With the virus, I would have thought the science behind how we stay well would have been one the place where we put some trust.

"In church we pray for people who are sick, but hope the doctors do their best. Some challenge is appropriate, but we see what can happen if everything becomes a matter of opinion. It happened in Bible times when the prophets said, `Everyone went their own way. Its a recipe for chaos."

Ross said his favorite Scripture regarding astronomy is Psalm 19:

"The heavens declare the glory of God."

"C.S. Lewis said he thought those lines were some of the most beautiful written in the English language," he said. "Hes someone who had a real sense of how the stars and sky through the ages have spoken to religious people and nonreligious people."

Lewis "Narnia" series, he noted, makes use of stars and planets in their plots.

In 2014, the Star of Bethlehem Conference observed its 400th anniversary at University of Groningen in the Netherlands. The group was founded by Johannes Kepler, who wrote a theory contending there was an alignment of the planets.

"For me, its less the scientific search than the wonder," Ross said. "I got interested in Bethlehem Star from `Its a Wonderful Life."

The film opens on an image of a group of galaxies known as Stephans Quintet.

"(Director) Frank Capra had a lifelong interest in astronomy," Ross said. "He studied at what became Cal Tech. At the time, those galaxies were the definition of things to wonder about. Its key element of the storyline."

Last year, Ross spoke at festival in Seneca Falls, N.Y., which honors the film.

"Its not until George (Bailey) changes his perspective, its after that hes able to see the stars," Ross said. "Its after he comes back from the bridge that hes able to see the stars again."

Ross urges people to visit Stark County Wilderness Center Education Director Robin Gills Facebook page, which features information on stargazing.

"It doesnt take a group or gathering to enjoy astronomy," he said.

Reach Charita at 330-580-8313 or charita.goshay@cantonrep.com

On Twitter: @cgoshayREP

Original post:

Pastor-astronomer: Recent solar events are gifts of awe - Massillon Independent

For The First Time Ever, Astronomers Have Witnessed a Black Hole ‘Blink’ – ScienceAlert

Black holes don't glow - in fact, they're famous for doing the opposite. But if they're actively devouring material from the space around them, that material can blaze like a billion X-ray Suns.

And for the first time, astronomers have now seen that blaze mysteriously snuffed out, before gradually returning to brightness.

The supermassive black hole is a beast clocking in at 19 million solar masses, powering a galactic nucleus 275 million light-years away, in a galaxy called 1ES 1927+654.

Over a period of just 40 days, astronomers watched as its corona absolutely plummeted in brightness, before rising again to shine brighter than before.

"We expect that luminosity changes this big should vary on timescales of many thousands to millions of years," said physicist Erin Kara of the Massachusetts Institute of Technology (MIT).

"But in this object, we saw it change by [a factor of] 10,000 over a year, and it even changed by a factor of 100 in eight hours, which is just totally unheard of and really mind-boggling."

There are several components to the area immediately around a black hole. There's the event horizon; that's the famous "point of no return", at which even light speed is not sufficient to attain escape velocity.An active black hole also has an accretion disc, a huge disc of material swirling into the object, like water circling a drain.

And just outside the event horizon of an active black hole, around the inner edge of the accretion disc, is the corona.

This is a region of scorchingly hot electrons thought to be powered by the black hole's magnetic field, acting like a synchrotron to accelerate the electrons to such high energies that they shine brightly in X-ray wavelengths.

Astronomers first noticed something strange occurring in 1ES 1927+654 in 2018, when the All-Sky Automated Survey for Super-Novae (ASASSN) - an automated survey looking for bright flashes of light across the entire sky - caught an incredibly bright flare from the galaxy, 40 times its normal brightness.

This caught astronomers' attention, and they pointed a bunch of telescopes in the galaxy's direction to find out more. For a while, everything was pretty normal - but then, around 160 days after the flare, 1ES 1927+654's nucleus started to dim. Over a period of 40 days, the X-ray glow was totally snuffed out.

"After ASSASN saw it go through this huge crazy outburst, we watched as the corona disappeared," Kara said. "It became undetectable, which we have never seen before."

But then the brightness started to steadily climb again. By 300 days after the initial flare, the galaxy's nucleus was shining almost 20 times more brightly than it had been prior to the initial event.

"We just don't normally see variations like this in accreting black holes," said astrophysicist Claudio Ricci of Diego Portales University in Chile, and lead author of the study.

"It was so strange that at first we thought maybe there was something wrong with the data. When we saw it was real, it was very exciting. But we also had no idea what we were dealing with; no one we talked to had seen anything like this."

Astronomers are not entirely sure how black hole coronae are generated and powered. But if, as theorised, it has something to do with the black hole's magnetic fields, then the dramatic changes observed in 1ES 1927+654's black hole could have been caused by something disrupting those magnetic fields.

We know that black holes can change pretty rapidly when they capture and devour a star that ventures just a little too close. The star is torn apart in a process called tidal disruption, screaming a flare of bright light, before getting slurped beyond the event horizon to meet its mysterious fate.

And if a runaway star so happened to encounter 1ES 1927+654's black hole, the events could fit the observed changes in the X-ray radiation. First, the star is tidally disrupted, causing the initial flare. Then debris from the star could have temporarily disrupted the black hole's magnetic field, after which it rebuilt itself as the space around the black hole settled back into a more normal state.

And that could be an important clue for understanding the radius within which a magnetic field controls a black hole corona.

"What that tells us is that, if all the action is happening within that tidal disruption radius, that means the magnetic field configuration that's supporting the corona must be within that radius," Kara said.

"Which means that, for any normal corona, the magnetic fields within that radius are what's responsible for creating a corona."

If a star was responsible for the event, the team calculated that the tidal disruption had to have occurred within four light minutes of the black hole's centre, around half the distance between the Earth and the Sun.

But there could be some other reason for the light show.

We know that black hole coronae can vary in brightness, although generally that occurs on much longer timescales. It's possible that the extreme behaviour observed in 1ES 1927+654 is actually also pretty normal behaviour - we just haven't spotted it until now.

"This dataset has a lot of puzzles in it," Kara said. "But that's exciting, because it means we're learning something new about the universe. We think the star hypothesis is a good one, but I also think we're going to be analyzing this event for a long time."

The research has been published in The Astrophysical Journal Letters.

Read more:

For The First Time Ever, Astronomers Have Witnessed a Black Hole 'Blink' - ScienceAlert

Video astronomy: Bring the universe to your friends with Celestron’s RASA 8 telescope – Space.com

A new generation of optically "fast" telescopes, connected to compact high-resolution video cameras, is poised to disrupt amateur astronomy in a good way.

Such "video astrographs" can transform our lonely pursuit into a much more social hobby. These new scopes can also bring magnificent, colorful, magazine-quality astrophotography within reach of modest budgets even for those of us living near light-polluted cities.

Leading this new era of happy disruption: Celestron's Rowe-Ackermann Schmidt Astrograph (RASA, pronounced "RAHZ'suh"). The RASA is purpose-built to capture wide, flat fields of starlight without introducing false color and without smearing or stretching any individual star's appearance (the dreaded "coma" problem).

It's called an "astrograph" because it's designed solely for photography. Think of it as a giant camera lens. You cannot use it for visual astronomy; there's no hole in which to plop an eyepiece! RASAs come in three aperture sizes. We looked at the most affordable RASA 8-inch (20 centimeters).

Related: Best telescopes for the money 2020 reviews and guide

The other heroes of this joyful revolution are new video cameras made by ZWO, Atik, QHY, Meade, Orion, Altair, Celestron and others. These compact, high-resolution cams easily fit onto the RASA's front plate, just where the image comes together ("prime focus"). Their compact, generally cylindrical bodies block very little of the view.

The RASA gathers light so quickly, it takes only a few seconds for software to begin to build a stunning image on a live video monitor. And the view continues to improve as the data build. For live video astronomy, it's best to use a color camera.

Buy Celestron RASA 8 on Amazon.com | $1,699.99

Capture wide-field, deep-sky images in seconds with Celestron's 8-inch Rowe-Ackermann Schmidt Astrograph. The telescope has incredibly fast optics and an ultra-stable imaging system. It does not include a tripod and mounting system.

Aperture:203mm (8") |Focal Length:400mm (15.74") |Focal Ratio:f/2.0 |Length:628mm (24.7") |Weight:17 lbs. (7.7 kg) |Spectral range:390-800nm

Say the word "video" and most people think of something moving on a screen. But video astronomy is not about seeing motion in the sky. True, every star in the universe moves. Our own sun along with planet Earth is slashing through spacetime at about 220 kilometers per second, or 490,000 miles per hour. The fastest stars those booted out by supernova blasts or slung around by supermassive black holes rip along at more than 1,500 km/s. Our human eyesight evolved to catch motion: Threatening predators, enticing food, treacherous situations, sexy people. But most stars are so far from one another, they don't seem to move on time scales humans can easily notice. So why shoot starlight on video?

Video is a stream of still images. If you stack them up rather than stringing them out you can use software to build up the brightness, bring up the color, subtract out the self-noise of the camera. If the telescope is "fast," those images can quickly add up to a glorious ghost of stellar nebulosity, materializing on a monitor, right before your eyes: The births and deaths of stars revealed. Something deeply moving on a screen after all!

You'll frequently see a telescope described by its "f-number;" "f/11, f/6" and so forth. That's it's "focal ratio" it's the number you get if you divide the focal length (distance from the main mirror or lens to the point where the image comes into focus) by the aperture (diameter of the main mirror or lens).

The lower the f-number, the "faster" the telescope will collect light, so the brighter the image will be. But it also means the field of view will be wider and the magnification lower. Faster instruments are thus better for photographing big dim targets, like galaxies and nebulas, which tend to be more diffuse. Slower optics are better for small bright targets like planets, lunar features and star groups. The RASA, at f/2.2, is a speed demon, fuzzy object grabbing machine!

Long before the novel coronavirus washed across our planet, we amateur astronomers were experienced practitioners of social distancing, though not by choice or necessity. Astronomy has not exactly been the most communal of activities. One spends a long while setting up, plugging-in, aligning, calibrating, star-finding, pointing, focusing and fiddling. These require concentration, which means not interacting with people very much.

Even before we needed to keep 6 feet (2 meters) of distance from one another, it wasn't that easy to coax friends or family members out into the cold to wait their turn at the eyepiece. They were inclined to be nervous about damaging your expensive 'scope; self-conscious about the folks waiting behind them. They were often bent over and uncomfortable adapting their bodies to our oddly angled rigs. So, they usually took much less of a good long look than they really wanted. This was hardly conducive to collective enjoyment. What should have elicited a "WOW!" too often turned into a "meh."

Video astronomy also called "electronic-assisted astronomy" changes all that. A live monitor connected to the telescope, or a live feed to the Web, instantly brings back the fun. With the RASA, "a laptop, and a camera is all you need," Dylan O'Donnell told Space.com from his Byron Bay Observatory in eastern Australia. An internet marketer by day, and a topnotch astrophotographer by night, O'Donnell publishes the extremely helpful STAR STUFF YouTube channel.

"If you wish to use a portable device, like a phone or a tablet," he said, "the ZWO ASI Air (Wi-Fi camera controller), or an equivalent, can make portable astronomy a little bit easier than lugging around a computer." With such a rig and good internet connectivity, you can live-stream the wonder of the universe to many people isolated behind closed doors.

Even before we needed to keep 6 feet (2 meters) of distance from one another, it wasn't that easy to coax friends or family members out into the cold to wait their turn at the eyepiece. They were inclined to be nervous about damaging your expensive 'scope; self-conscious about the folks waiting behind them. They were often bent over and uncomfortable adapting their bodies to our oddly angled rigs. So, they usually took much less of a good long look than they really wanted. This was hardly conducive to collective enjoyment. What should have elicited a "WOW!" too often turned into a "meh."

Video astronomy also called "electronic-assisted astronomy" changes all that. A live monitor connected to the telescope, or a live feed to the Web, instantly brings back the fun. With the RASA, "a laptop, and a camera is all you need," Dylan O'Donnell told Space.com from his Byron Bay Observatory in eastern Australia. An internet marketer by day, and a topnotch astrophotographer by night, O'Donnell publishes the extremely helpful STAR STUFF YouTube channel.

"If you wish to use a portable device, like a phone or a tablet," he said, "the ZWO ASI Air (Wi-Fi camera controller), or an equivalent, can make portable astronomy a little bit easier than lugging around a computer." With such a rig and good internet connectivity, you can live-stream the wonder of the universe to many people isolated behind closed doors.

As a member of Team Celestron, O'Donnell was one of the first to put the RASA through real-world, gotta-get-the-shot demanding paces. "I have used the RASA for live video style astronomy and these f/2 scopes are perfect," he said. "Some software like SharpCap and [Howie Levine's] Astro Toaster can provide live stacking features, which will build up an image from short exposures fairly quickly on-screen, while removing the noise and making astronomya much quicker, more visceral experience. At outreach events this techniquecan be very impressive with a projector!"

Watch Dylan O'Donnell mount a camera on the RASA 8.

When we are able to congregate again, this formerly lonely, arcane hobby can quickly become an enjoyable shared experience like a cool concert or the big game on a wide screen. Just please check, if you're planning on doing this at a classic star party, that your bright monitor will be allowed. Don't you dare despoil the dark for visual observers!

Astronomical get-togethers don't have to exist only in real time and real space. Social media shifts the star party through the fourth dimension: Posting the proud astrophoto you just made by stacking and tweaking last night's imaging run is a wonderful conversation starter.

Beyond grabbing live images for a display, video astronomy on the RASA can also dredge ancient light waves from the abyss much faster than nearly every other telescope. To get the sharpest images of the deep sky, it's best to switch to a monochrome camera and capture one portion of the spectrum at a time ("narrowband imaging").

The RASA 8's relatively small aperture means you can't use big motorized filter wheels; you have to manually insert single filters along the optical path to your camera. But this can be very worthwhile if you live under light pollution; so-called notch filters and sky filters can subtract artificial light from your images of the sky.

If you grab a number of exposures in sets, each optimized for recording key wavelengths, your final stacked astrophoto can reveal structure in the universe that was invisible to the largest observatories on Earth 40 years ago.

Thanks to the RASA's optical speed, you can do in 2 hours what other instruments can barely manage over two nights. And such a system can get good images under surprisingly light-polluted locations near cities. O'Donnell's "RASA 8 First Light Review" video will show you just what's possible.

Even though the RASA is fast, you still need it to accurately track a point on the sky. That demands a motorized mount under computer control.

Start by performing the best polar alignment you can. Then, "you really want to be guiding and dithering if possible," O'Donnell said, "so you'll need a guide-scope and camera connected to your imaging computer."

To "dither" means to slightly nudge the telescope in a different random direction each time you start a new exposure. This makes it easy to find and kill bad pixels (from the camera's sensor), satellite streaks (there are soon to be many more of these!), or any other consistent artifacts when you stack the shots to make your final composite.

Beyond dither, there's drizzle. A technique originally developed to perfect the historic Hubble Deep Field images is now available to you, the amateur astrophotographer. Drizzling technically known as "variable pixel linear reconstruction" can be invoked at the image-processing stage to restore information lost to under-sampling (one can only expose for so long). Drizzling on your image data can correct small geometric distortions caused by variability in the optics; the astrograph and the camera are excellent, but not perfect:

"One of the reasons the RASA 8 works so well is because the sampling is so good for popular cameras," O'Donnell said. "However, as the field is so wide, stars appear quite small and may feel blocky." But dither (as you're shooting) and drizzle (as you're stacking) can repair the downside damage done by wide-field image capture. Watch O'Donnell break down the whole workflow into simple, easy steps in his video, "Taking Photos of Space."

RASA Optical Tube Assemblies (OTAs) just the telescope itself, no mount, no tripod of three different dimensions are currently available: The RASA 8-inch (20 cm) can be found for about $1,700. Stepping up to the RASA 11-inch (28 cm) will cost around $3,500. You can watch O'Donnell's RASA 11 review video here.

At the high end, Celestron has also developed the research-grade 36 cm (14-inch) aperture RASA targeted to institutions, companies and agencies involved in space surveillance. Many of these big RASAs work to monitor space junk that can damage communications data satellites. Others stalk comets and near-Earth asteroids. A few are at work examining galaxies and galactic clusters.

Buy Celestron RASA 8 on Amazon.com | $1,699.99

Capture wide-field, deep-sky images in seconds with Celestron's 8-inch Rowe-Ackermann Schmidt Astrograph. The telescope has incredibly fast optics and an ultra-stable imaging system. It does not include a tripod and mounting system.

Aperture:203mm (8") |Focal Length:400mm (15.74") |Focal Ratio:f/2.0 |Length:628mm (24.7") |Weight:17 lbs. (7.7 kg) |Spectral range:390-800nm

Beyond price, the RASA 8 can claim two more advantages: It has a wider field of view than its siblings, letting you seize big celestial vistas, like the Orion Nebula, in a single frame. "That 400-millimeter focal length results in quite a wide field of view," O'Donnell told Space.com, "so unless you're looking at Andromeda, this telescope is less of a galaxy hunter and more of a big nebula monster!"

And the RASA 8 is also eminently transportable. The smaller 8-inch OTA can be used on a less expensive smaller mount, atop a more compact tripod; making it easier to get your rig out to dark-sky sites for better images or to travel your sky-sharing machine at star party locations.

The RASA 8's smaller size, though, limits the size of the camera you can fit to it. Your old DSLR is too big. So, probably, is a full-frame video sensor. In fact, the RASA 8 is pretty much limited to APS-C (Advanced Photo System type-C) cameras of the popular Micro Four Thirds format. But there are a lot of them to choose from

To pick the right camera for your needs, it's best to work with a qualified astronomy store. The area at which the RASA 8 can focus is quite tightly bound; your camera's sensor must be in that zone and only certain cameras will succeed. We worked with expert reseller David Barrett at High Point Scientific to configure our rig.

The vast majority of stars even most of those in our own galaxy can't be seen without a telescope collecting their light and a camera storing that light. Stare as you might into the night, you won't see what a "time exposure" can record. To see color and find structure in the cosmos, you must collect that light over time, storing it as a long-exposed image and, perhaps, stacking many such images. With a typical "optically slow" telescope, this can take many hours outside often over several nights and more inside, processing and tweaking at the computer. Astrophotography has, up until now, taken great patience and almost monastic meditation characteristics with which few of us are abundantly blessed.

Telescope optical designs each have differing capacities to gather photons (or particles of light) from far away. The faster a scope can grab them, the less Earth has time to rotate. The RASA can grab a basic monochrome ("black and white") image of any of the better known "fuzzies" (such as the Andromeda Galaxy or the Orion Nebula) in about a minute, with no need to guide the scope. A typical Schmidt-Cassegrain telescope (SCT) of the same aperture will need at least 13 minutes to get a similar image. And the SCT will need to be precisely polar-aligned and actively tracking the whole time, as Earth noticeably rotates.

In camera terms, the RASA is like a lens rated at f/2.2. That's very "fast." Only the highest quality prime lenses used by cinematographers typically deliver that performance. By comparison, the average SCT or Richey-Chretien ("R-C" like the Hubble Space Telescope) works no faster than f/10. Telescope designers use a more precise T-number, which takes into account light stolen by internal structures. The RASA is a T/2.5 system; a typical SCT does no better than about T/11.

Magnification is not the RASA's strong suit. Each of the three RASAs is a wide-field light bucket, best for bagging large, dim objects like nebulas and large (nearby) galaxies, but also for discovering asteroids, comets and locating human-made space junk. It's not for planets. If you're interested in investigating for yourself if Jupiter's Great Red Spot is really shrinking, get hold of a good apochromatic refractor.

Related: Best telescopes for beginners 2020 guide

At first, the idea seems kludgy: You plop a blob of video camera in the middle of the front end of an expensive telescope, so it sticks out into the night like a narwhal's tusk. Add to that the insult of a couple of draped cables: data (video) and power. Aren't you obstructing the most vital part of the light-collector? Well, no, you're not. A hybrid "catadioptric" telescope takes light in around the ring of its big "corrector plate" at the front, then bounces it off a large mirror at the back. In the more familiar Schmidt Cassegrain (SCT) or Maksutov Cassegrain (Mak-Cas) telescopes, that light is bounced one more time, off a small secondary mirror, and exits through a hole in the primary mirror where your eyepiece lies waiting.

With no eyepiece, RASA has no need for such a hole. Part of the genius of the Rowe-Ackermann Schmidt Astrograph (and its ancestors, the Fastar and HyperStar camera retrofits) is to bring the image to prime focus after just one bounce. So that's where you put your camera. You can't put an eyepiece there; your head would block most of the aperture.

The back-shell of the RASA contains an electric fan and a separate flow-through vent-port to help bring the optics into thermal equilibrium with the world around them. Differences in temperature across the glass surfaces can play hob with your focus, making your star field look like it's printed on Silly Putty. The RASA's fan gets 12-volt power from a battery pack or your power tank; that's one of several cables you'll need to run.

You'll also need to cable the camera. Outside of smartphones, there aren't yet many small, wireless high-quality video cameras. Perhaps with 5G network sprouting up everywhere (soon!), demand for such a "little beastie" will develop. Until then, we'll have cables in our fields of view. Those wires will introduce diffraction spikes into your images. But if you dress your cables out at 90 degrees, you'll get that classic four-pointed spiky star effect, which a lot of viewers find pleasing.

As the Apollo 11 crew was headed for the moon, the first charge-coupled device (CCD) image chip was being developed at Bell Labs in New Jersey. CCDs soon replaced the fragile and finicky tubes in video cameras. I first saw one applied to a telescope in 1985, at the observatory complex on Mauna Kea in Hawaii.

Modern barrel CCD astrophotography cameras are spectacularly "quiet" (low visual noise), especially when actively cooled. But they suffer from occasional "hot" pixels (individual full-white errors of quantum accumulation). And they will sometimes "bloom" (introduce a shaped glow) across the frame. CCDs take wonderfully detailed images, but they take a while to do so.

Gaining on CCDs in quality and available at lower cost are CMOS (Complementary Metal Oxide Semiconductor) sensors. They tend to be noisier than CCDs. But that noise is of a different, more subtle character. And CMOS sensors can be made smaller than CCDs, with much higher pixel densities. The cameras in your phone are CMOS. CMOS logic is fast; a quicker exposure through a telescope means a lower chance that motion-tracking errors will build up to distort your celestial portraits.

If your main focus (a poor pun) is on planets, Earth's moon or the sun, you'd be well advised to look to a CMOS solution first. Just please note that wide-field OTAs like the RASA are not good at small targets. If you crave distant galaxies and have, perhaps, a bit more disposable income for your astrophotography hobby look into one of the higher end scientific CCD cameras, which operate at 16 bit-depth.

Whether CCD or CMOS, shooting stars with dedicated video cameras gives you the advantage of active cooling, which reduces electronic noise. Your old DSLR doesn't have a fan (and it's too big to use on the RASA 8 anyway.)

Starting in the 1930s, a few professional observatories built large telescopes with cameras inside them. Designed by the Estonian optician Bernhard Schmidt, these instruments boasted fast focal ratios and very wide-field views. But changing the film was cumbersome. And servicing the camera meant taking most of the telescope apart.

The ability of these "Schmidt cameras" to seize broad swaths of sky quickly enabled many asteroid discoveries, supernova surveys and captured the earliest clues to the existence of the attractive force of dark matter and repulsive force of dark energy.

Starting in the 1970s, many of these grand old instruments were upgraded with some of the first CCD detectors in place of the film cameras. At first, CCDs were very expensive; in many cases, custom made. (One of the largest Schmidt cameras, the 48-inch (1.2 m) Samuel Oschin Telescope at the Palomar Observatory in California, has been upgraded with five successive CCD generations.)

In the late 1970s, telescope manufacturers serving the amateur market began to offer Schmidt optical tubes with 35-mm film holders inside, advancing amateur astrophotography beyond the self-made, bespoke rig level.

As the new century approached, and CCDs further displaced film, Celestron introduced its Fastar camera, designed to retrofit stock Schmidt-Cassegrain telescopes (SCTs). Owners would amputate the telescope's small secondary mirror, replacing it with the Fastar. This meant they could no longer observe by eye, but could concentrate starlight on the Fastar's 320-by-240-pixel CCD; quite primitive by today's 3,840-by-2,160-pixel ("4K") standards, but amazing for the time.

In the early 2000s, the owners of Starizona, an astronomy enthusiasts' store in Tucson, Arizona, propelled the hobby of astrophotography forward with the innovative HyperStar retrofit kits. Owners could now attach their new DSLR (Digital Single-lens Reflex camera), or small CCD video camera, to their SCT. Wide-field electronic images, garnered by fast telescopes with short focal lengths, were now possible. But only certain telescopes could be converted. Smaller apertures would be useless with big DSLR cameras hanging on the front, blocking light. And it wouldn't have made good business sense for Starizona to create a kit for every existing type and size SCT in service.

Around 2013, the Celestron Co. came to an internal consensus that a dedicated fast, wide, astrograph a telescope tube built specifically as a camera "lens" could open astrophotography to many more amateur observers. Pioneering designs by David Rowe, and innovative improvements from Mark Ackermann, challenged Celestron's engineers to bring an affordable mass-produced astrograph to market. Rowe and Ackermann were honored as the "R" and "A" in RASA. And the RASA 11 was born.

Driven by consumer demand for better digital cameras and imaging smartphones, video sensors continued shrinking even as they grew in pixels. This spawned the clutch of less-massive, purpose-built astrophotography cameras available today. With smaller bodies generally cylindrical in shape such cameras obscure less of the telescope's working area, making it possible for Celestron to offer the RASA design concept in a more affordable 8-inch aperture footprint.

Remember those grand old Schmidt tubes with the film cameras inside? Now, as video cameras contract, it's possible the next generation of consumer telescopes, beyond RASA, might put the camera back inside the tube, more or less permanently mounted. Ubiquitous 5G network connectivity could make the camera, the astrograph OTA and the computer-driven tracking mount all completely wireless.

Time will tell. In the meantime, fast (f/2) wide field telescopes like RASA, and compact, 4K video cameras are here now, producing wonderful images that are easy to post and distribute. Every one of us is a stakeholder in the universe. Help your friends to claim their share.

This article was prepared using the following equipment:

Follow the author @DavidSkyBrody. Follow us on Twitter @Spacedotcom and on Facebook.

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Video astronomy: Bring the universe to your friends with Celestron's RASA 8 telescope - Space.com

Solar Orbiter sends back the closest photos of the Sun ever taken – Astronomy Magazine

Another instrument, the Solar and Heliospheric Imager (SoloHI), sent back shots of the zodiacal light, which occurs when sunlight reflects off dust particles in our solar system. Although these images dont signify a new discovery, taking them required SoloHI to tamp down the Suns glare to just a trillionth its actual brightness. By successfully completing the task, researchers are confident SoloHI can produce the image quality needed to study the solar wind (the instruments intended purpose) once the mission ramps up.

The Polarimetric and Helioseismic Imager (PHI) also beamed back high-resolution data showing the Suns intricate and powerful magnetic field. And in a first, PHI revealed a view of a local magnetic field on the Sun that was not visible from Earth at the time, exemplifying just one advantage of the spacecrafts intentionally tilted orbit.

The Suns magnetic field drives numerous internal processes, which can produce solar flares and other powerful outbursts. Such energetic solar events can affect us here on Earth, too from sparking stunning auroras to knocking out satellite communications and earthbound power grids. But by monitoring the Sun with spacecraft such as Solar Orbiter and the Parker Solar Probe, scientists should be able to better predict when Earth-affecting space weather will occur.

All in all, these first results show that we still have much to learn about our home star, as well as the forces that power its frequently finicky behavior. Solar Orbiter is off to an excellent start, said project scientist Daniel Mller. We are all really excited about these first images but this is just the beginning.

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Solar Orbiter sends back the closest photos of the Sun ever taken - Astronomy Magazine


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