Monthly Archives: June 2021

Using a new observatory, a team of Chinese astronomers have found over a dozen sources of ultra-high energy cosmic rays. And those sources arent from some distant, exotic corner of the cosmos. They come from our own backyard.

Ultra-high energy cosmic rays (UHECRs) arepretty energetic, typically millions of times more energetic than our most powerful particle accelerators. They are also relatively rare, and so astronomers have had a hard time pinpointing their origins.

But a team of Chinese scientists led by Institute of High Energy Physics (IHEP) under the Chinese Academy of Sciences dug deep into the origins of UHECRs using the recently-built Large High Altitude Air Shower Observatory (LHAASO). LHAASO is currently under construction in Daocheng in southwest Chinas Sichuan Province, but the astronomers were able to use the completed half of the instrument for an 11-month observation run.

They found a dozen sources of UHECRs, as well as some high-energy photons, including one with an energy of 1.4 Peta-electron volts (quadrillion electron-volts or PeV), the most energetic photon ever observed.

All those sources sit within the Milky Way.

These findings overturn our traditional understanding of the Milky Way and open up an era of UHE gamma astronomy. These observations will prompt us to rethink the mechanism by which high-energy particles are generated and propagated in the Milky Way, said Cao Zhen, chief scientist of LHAASO.

In addition, these observations will encourage us to explore more deeply violent celestial phenomena and their physical processes, as well as to test basic physical laws under extreme conditions, Cao said.

The sources of the UHECRs include a variety of natures own particle accelerators: newly-formed giant stars, supernovae explosions, massive star clusters, pulsar wind nebulae, and more.

The entire facility of LHAASO will be completed in 2021. With the completion of LHAASO and continuous data accumulation, we can anticipate finding an unexplored UHE universe full of surprising phenomena, He Huihai with the IHEP added.

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Astronomers Have Tracked Down the Source of High Energy Cosmic Rays to Regions Within the Milky Way Itself - Universe Today

The concept design of the LUVOIR space telescope would place it at the L2 Lagrange point, where a ... [+] 15.1-meter primary mirror would unfold and begin observing the Universe, bringing us untold scientific and astronomical riches. From the distant Universe to the smallest particles to the lowest temperatures and more, the frontiers of fundamental science are indispensable for enabling tomorrow's applied science frontiers.

When it comes to uncovering the ultimate truths about reality, we can only reap what we sow. Without a cutting-edge particle collider like the Large Hadron Collider at CERN, we would never have discovered the Higgs Boson. Without the incredible sensitivities achieved by gravitational wave detectors such as LIGO and Virgo, we never would have directly detected gravitational waves. And without a revolutionary space telescope like Hubble, the overwhelming majority of the Universe which has since been revealed to us in exquisite detail would have remained obscure.

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In our quest to understand the Universe around us, we always seek to extract the maximum amount of science possible from whatever tools we choose to build. Once every 10 years, the entire astrophysics community gets together to submit their recommendations for which projects would be of the greatest scientific benefit to the field: part of a decadal survey conducted by the National Academies. These surveys have brought us some of the most iconic missions in history, and have helped advance science like nothing else ever has. In just a few months, theyll release their decision on recommendations for the four astrophysics missions that made it as finalists. With the results yet to be revealed, theres one proposed observatory that everyone should know about: LUVOIR. If youve ever dreamed about knowing the answers to the biggest questions of all, this is the one telescope that we absolutely must build. Heres why.

The Hubble Space Telescope, as imaged during its last and final servicing mission. Although it ... [+] hasn't been serviced in over a decade, Hubble continues to be humanity's flagship ultraviolet, optical, and near-infrared telescope in space, and has taken us beyond the limits of any other space-based or ground-based observatory.

For the past 31 years, NASAs Hubble has truly showcased for us what a cutting edge, space-based observatory is capable of. Far above the atmosphere of Earth, Hubble:

In fact, the limiting factor to Hubbles equipment the reason it cant observe at wavelengths longer than about 2 microns, or about three times as long as the limit of human vision is because it gets heated by the Sun. Just as infrared cameras reveal heat sources, the inside of Hubble is too warm to observe at mid-and-far infrared wavelengths.

The visible light (L) and infrared (R) wavelength views of the same object: the Pillars of Creation. ... [+] Note how much more transparent the gas-and-dust is to infrared radiation, and how that affects the background and interior stars that we can detect. These infrared views are limited by the temperature of Hubble: without a cooler telescope, it cannot measure longer-wavelength light.

Hubbles other major limitation is its narrow field-of-view. Even with the most advanced camera ever installed on it, the Advanced Camera for Surveys/Wide Field Camera 3, it can only achieve resolutions of approximately 8 megapixels. When you take into account the mirror size and focal length of Hubble optical properties that are second nature to astronomers it can resolve objects down to angular resolutions of just 0.04 arc-seconds, or just one-ninety-thousandth of a degree. If you put the Hubble Space Telescope in New York, it could resolve two separate fireflies in Tokyo if they were separated by merely 3 meters (10 feet).

This makes Hubble outstanding at taking deep, high-resolution observations in the ultraviolet, optical, and near-infrared, over small fields-of-view. Various observing campaigns, like the Hubble Deep Field, Ultra Deep Field, and eXtreme Deep Fields, have taken advantage of these capabilities to reveal what lies out there in the abyss of deep space: thousands upon thousands of galaxies in tiny regions of space that cover mere fractions of a millionth of the sky.

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The Hubble eXtreme Deep Field (XDF) may have observed a region of sky just 1/32,000,000th of the ... [+] total, but was able to uncover a whopping 5,500 galaxies within it: an estimated 10% of the total number of galaxies actually contained in this pencil-beam-style slice. The remaining 90% of galaxies are either too faint or too red or too obscured for Hubble to reveal.

Yet even at the full extent of its capabilities even with the equivalent of a month of continuous observing Hubble can still only see an estimated ~10% of the galaxies that are out there. Most of them are some combination of:

to be seen by Hubble. Moreover, even the majority of galaxies that are revealed are barely more than a few points, as Hubble is too small in size, with too little resolving power, to reveal additional details. In many ways, Hubble represents the greatest astronomical endeavor ever undertaken by our civilization, but its also fundamentally limited.

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Over the coming decade, beginning later this year, two additional space-based NASA observatories will launch: the James Webb Space Telescope, which is larger, cooler, and can work with much longer wavelengths than Hubble can, and the Nancy Roman Telescope, which is very similar to Hubble except with wide-field capabilities and much more powerful, state-of-the-art cameras.

The Hubble Ultra-Deep Field, shown in blue, is currently the largest, deepest long-exposure campaign ... [+] undertaken by humanity. For the same amount of observing time, the Nancy Grace Roman Telescope will be able to image the orange area to the exact same depth, revealing over 100 times as many objects as are present in the comparable Hubble image.

These observatories will begin to tackle some of the questions that Hubble cannot answer. With its enormous sunshade, its location far beyond both the Earth and the Moon, its on-board active coolant, and its enormous, gold-coated 6.5-meter primary mirror, James Webb will surpass Hubble on many fronts. Instead of ~2 microns, it can observe wavelengths out to ~30 microns, revealing an enormous suite of science details that Hubble cannot. From the earliest stars and farthest galaxies to details about planet formation and the atmospheric composition of the closest Earth-like planets around the smallest stars, this observatory is truly the next leap forward for space-based astronomy.

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The Nancy Roman Telescope, on the other hand, will go broad, wide, and just as deep as Hubble. With its wide-field views, each observation will collect 300 megapixels of data compared to Hubble 8, enabling large, deep, wide-field surveys to be done in just a tiny fraction of the time. Roman will shine brightest when it comes to observing projects like the ones that created the Hubble Frontier Fields or that imaged the Andromeda galaxy. Instead of months of observing time, Roman could do it in mere hours.

The streaks and arcs present in Abell 370, a distant galaxy cluster some 5-6 billion light years ... [+] away, are some of the strongest evidence for gravitational lensing and dark matter that we have. The lensed galaxies are even more distant, with some of them making up the most distant galaxies ever seen. This cluster, part of the Hubble Frontier Fields program, could be imaged in less than 1% of the time it took Hubble to do it with LUVOIR.

But even with these advances, there are still questions that we want answers to big, important, even existential questions that will go unanswered. Even with Webb and Roman, most of the galaxies in the Universe, even in a tiny, narrow region of space, will remain elusive. Most of the galaxies that we do see will still, unfortunately, simply be a few pixels across, with barely discernible structure. And, perhaps most importantly, they wont have the ultimate capabilities of a space-based observatory: the ability to directly image Earth-sized planets around Sun-like stars, and to identify which ones might not only have signatures for life, but might actually be inhabited.

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There is one telescope thats been designed that could accomplish all of these, and its one of the four finalists to determine what NASAs plan for astrophysics flagship missions will be for the 2030s: LUVOIR.

The Hubble Space Telescope (left) is our greatest flagship observatory in astrophysics history, but ... [+] is much smaller and less powerful than the upcoming James Webb (center). However, in order to get the resolution and contrast necessary to determine the atmospheric contents of an Earth-sized planet around a M-class star like TOI 700 located ~100 light-years away, a more powerful telescope, such as the proposed LUVOIR observatory, will be necessary.

What is LUVOIR?

Its the Large UltraViolet, Optical, and InfraRed telescope. Basically, you should imagine a version of the largest functional ground-based telescopes we have operating today telescopes like the ones at Keck Observatory or the Gran Telescopio CANARIAS equipping it with the greatest instruments that modern technology can offer, and launching it into space. Thats LUVOIR.

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In terms of what LUVOIR will bring us, its hard to overstate just how powerful an observatory like this would be. Sure, its technical specifications are impressive, but whats really impressive is how it will help answer some of the biggest questions we have about the Universe today.

Is 'Planet Nine' real? The science is still uncertain. But if it does exist, most ground-based ... [+] telescopes or even current/future space-based telescopes will be barely able to image a single pixel's worth of it. But LUVOIR will be able, even at its great distance, to reveal intricate structure on the surface of the world.

1.) Are there any inhabited planets nearby? Note the use of that word: inhabited. Were not talking about looking for potentially habitable worlds, nor worlds with bio-hints or bio-signatures, nor words that might be capable of someday being home to humans. Were talking about the big one: finding out if the nearest Earth-like planets actually have life on them. And were not talking about one or two nearby planets, but dozens, and potentially even hundreds.

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Well not only be able to directly image these worlds with LUVOIR, well be able to determine:

As LUVOIR scientist Jason Tumlinson said, it could explore dozens or Earth-like planets and assay their atmospheres. Detecting an exoplanet showing signs of life would be a discovery on the level of Newton, Einstein, Darwin, quantum mechanics, Hubbles expansion - you name it. LUVOIR is the first telescope designed from the beginning for this revolutionary purpose.

A simulated view of the same part of the sky, with the same observing time, with both Hubble (L) and ... [+] the initial architecture of LUVOIR (R). The difference is breathtaking, and represents what civilization-scale science can deliver.

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2.) The ability to finally reveal almost all of the objects that Hubble, Webb, and Roman will overlook. With LUVOIRs size, optical capabilities, and novel instrumentation, it will surpass all previous limits in terms of what it can discover. The jump from Hubble, at the absolute limit of the faintest objects in the eXtreme Deep Field, to LUVOIR will reveal objects a whopping 40 times fainter than we can presently see. Thats the same leap from large, ground-based telescopes to Hubble, or from a 30-second exposure with a 2-meter telescope to an all-night exposure with the largest telescopes presently in the world.

Basically, if youre looking for objects that are faint, far away, small, or otherwise difficult to characterize, LUVOIR will not only find it if you know where to look, but it can tell you far more about its details than any other tool.

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A simulated image of what Hubble would see for a distant, star-forming galaxy (L), versus what a ... [+] 10-15 meter class telescope like LUVOIR would see for the same galaxy (R). The astronomical power of such an observatory would be unmatched by anything else: on Earth or in space. LUVOIR, as proposed, could resolve structures as small as ~1,000 light-years in size for every single galaxy in the Universe.

3.) What does any galaxy in the Universe, in detail, look like? Imagine being able to point your telescope at any galaxy in the Universe an object typically around 100,000 light-years across and no matter how far away it is, still being able to see features in it as small as ~300 light-years across. For a galaxy the size of the Milky Way, no matter how distant it is from us, LUVOIR would show it as at least 400 pixels across, containing over 120,000 pixels of useful, luminous information in every frame.

The same galaxy, if it were imaged with Hubble in the same amount of time, would contain only 0.06% of the information contained in a LUVOIR image, with vastly inferior resolution and light-gathering power. We could learn:

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and so much more. From objects within our Solar System to exoplanets, stars, galaxies, and the largest cosmic structures of all, LUVOIR would answer the biggest questions we have about our Universe. All we have to do, to make our dreams of knowing whats out there in the Universe come true, is choose to build it.

Lynx, as a next-generation X-ray observatory, will serve as the ultimate complement to optical ... [+] 30-meter class telescopes being built on the ground and observatories like James Webb and WFIRST in space. Lynx will have to compete with the ESA's Athena mission, which has a superior field-of-view, but Lynx truly shines in terms of angular resolution and sensitivity. Both observatories could revolutionize and extend our view of the X-ray Universe.

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We owe the greatest space-based observatories in history to decadal surveys conducted in the recent past. Theyve brought us telescopes like Hubble, Spitzer (infrared), Chandra (X-rays), and will be bringing us the upcoming Webb and Roman telescopes as well. The current decadal survey, which charts the course for astronomys future in space, has four excellent options, but only one has the power to reveal whether dozens or even hundreds of potentially habitable worlds are, in fact, inhabited: LUVOIR. Its the one observatory that could revolutionize astronomy over and over again, possibly for as long as the remainder of the 21st century.

But the ultimate hope is that we wont just build LUVOIR the best of the present options but an array of observatories, one after the other, that will all cover different wavelengths and work to complement one another. Origins, a far-infrared telescope, is ideal for measuring details about planets and stars still in the process of forming. Lynx, an X-ray telescope, could reveal details about black holes, neutron stars, and colliding galaxies that nothing else can see. Even HabEx, an exoplanet-optimized mission inferior to LUVOIR in every way, could launch on a much shorter timescale, making it an attractive option.

As the head of NASAs astrophysics division, Paul Hertz, put it, I want all of these missions to fly. I think we should do them all; the decadal survey should tell me which one to do first.

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While HabEx will be a quality all-purpose astronomical observatory, promising much good science ... [+] within our Solar System and of the distant Universe, its true power will be to image and characterize Earth-like worlds around Sun-like stars, which it should be able to do for up to hundreds of planets close to our own Solar System. It still won't have the capabilities of LUVOIR, however.

When the National Academies release their recommendations in just a few weeks, the great hope of astronomers is that at least three of these missions will be chosen to move forward, with LUVOIR, the most powerful and ambitious space-based observatory ever proposed, as the top choice. If we want definitive answers to the biggest questions of all, it takes a big effort and a substantial investment. Considering that the reward is learning that theres life on that planet, orbiting another star, right over there, its clear that LUVOIR is the one telescope we must all join together to build.

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Astronomers To NASA: Please, Build This Telescope! - Forbes

Astronomy tends to have a timeless feel to it. Stars take millions of years to be born, a given galaxy will look exactly the same today as it did at the height of the Maya empire, even the constellations in the sky look pretty much the same as they did when Indigenous Australians started weaving their stories about them so very long ago in human terms.

Sometimes, though, things happen on a much faster timescale. The Stingray Nebula can lay claim to two such rapid events: It probably only started glowing about 40 years ago, and it faded substantially over just twenty years of that time!

The Stingray Nebula technically called Henize 3-1357 is what we call a planetary nebula, gas ejected by a star similar to the Sun as it dies. When such a star runs out of nuclear fuel in its core to fuse, the outer layers swell up and the star becomes a red giant. It then starts to shed the gas making up those outer layers, blowing a wind of material into space.

A lot of gas is blown off this way, so much so that deeper and deeper layers of the star get exposed. Eventually what remains is the star's core, a hot, dense white dwarf, which blasts out ultraviolet light and causes the surrounding gas to glow. The shapes that gas forms can be very strange as winds blown later catch up with and slam into slower material ejected earlier, for example. Magnetic fields, stellar spin, binary companions, and more can all sculpt the nebula into fantastic shapes.

The Stingray Nebula surrounds the star SAO 244567, what's called an asymptotic giant branch star. This means that it's already been a red giant for a while, and is well on its way to shedding its final outer layers. It obviously has been for some time, since the nebula exists, and given measurements of the gas itself (how it's expanding away from the star) it's likely SAO 244567 has been belching out gas for a thousand years or so.

In the late 1980s or early '90s something changed, though. The star started getting hotter... a lot hotter. It went from about 21,000 C in 1980 (much hotter than the Sun's 5500) to a face-melting 60,000 by 2002. At the same time it shrank in size this was determined by carefully measuring spectra taken of its light. Astronomers think that it had what's called a late thermal pulse, where gas under incredible pressure in a shell around its core underwent furious rates of fusion, heating the star up.

This extra light zapped the gas already blown out by the star, lighting it up, causing it glow literally like a neon sign. That is, electrons in the gas atoms jumped up in energy levels, then emitted light when they dropped back down. That's when it would've first been visible from Earth, making it the youngest planetary nebula ever seen.

But then the star started to settle down. By 2015 the temperature had dropped to 50,000 and the star swelled back up again.

What all this means to the nebula is that between 1996 and 2016 the gas faded considerably.

As you can see, it looks a lot different in the after shot than the earlier one. To be clear, the structure of the nebula is probably almost exactly the same; that hasn't changed much at all. What has changed is that it's faded, and in some places it's faded a lot.

For example, the outer lobes forming that broad and thick X are gone in the later image. Those have squiggly filaments of gas in them that gave the Stingray its name, but now they're too faint to see. Both images are color-coded the same way; blue light is from oxygen, green from hydrogen, and red from nitrogen. When hit by UV light they respond differently. For example, oxygen fades rapidly, even more so where the gas is dense. The lobes and inner region are heavy with oxygen and have faded the most, in some places by a factor of 900.

This fading does allow astronomers to probe the structure and nature of the nebula; it's possible to determine things like the gas density and temperature, and what exactly it's doing. Sometimes, for example, some gas glows as it slams into other gas, but in this case it looks like everything in the nebula depends on the star to glow.

So what's the fate of this nebula? It may very well continue to fade, even so much Hubble won't be able to see it. However, once the outer layers are completely blown off and the white dwarf is revealed, it will likely light up once again. That may not be for decades or even centuries, though.

Our own Sun will likely go through similar paroxysms when it's in a similar stage, about 7 billion or so years from now. Most likely our future planetary nebula it won't have such a cool shape with all that structure, but it may very well get brighter and dimmer over time, until the Sun blows off its envelope and becomes a white dwarf.

When we study planetary nebulae like the Stingray we learn more about or own distant future. And it amazes me to think that after 11+ billion years of life, the Sun will do this as well, possibly changing significantly over just a few years after all those eons.

Will future astronomers half a galaxy away oooo and ahhhh over its behavior? Who can say. But it's nice to know that even in stellar death there is awe and beauty.

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The rise and rapid fall of the Stingray Nebula - SYFY WIRE

A view of the telescope domes on the roof of the Vatican Observatory, at the Apostolic Palace in Castel Gandolfo, in 2015. Andreas Solaro/AFP via Getty Images hide caption

A view of the telescope domes on the roof of the Vatican Observatory, at the Apostolic Palace in Castel Gandolfo, in 2015.

CASTEL GANDOLFO, Italy At a time of growing diffidence toward some new scientific discoveries, the one and only Vatican institution that does scientific research recently launched a campaign to promote dialogue between faith and science.

It's the Vatican Observatory, located on the grounds of the papal summer residence in Castel Gandolfo, a medieval town in Alban Hills 15 miles southeast of Rome.

The director, Brother Guy Consolmagno, is giving this reporter a guided tour of the grounds. We drive along a cypress-lined road, admiring majestic gardens and olive groves nestled near the remains of a palace of the Roman Emperor Domitian, before reaching a field with farmworkers and animals.

"This is the end that has the papal farm, so you can see the cows the papal milk comes from," Consolmagno says as he points out the working farm that provides the pope at the Vatican with vegetable and dairy products.

(Pope Francis, known for his frugality and habit of not taking vacations, decided not to use the papal summer villa, which he considers too luxurious. But he ordered the estate become a museum open to the public.)

For most of its history, the Catholic Church rejected scientific findings that conflicted with its doctrine. During the Inquisition, it even persecuted scientists such as Galileo Galilei.

In the Middle Ages, it became apparent that the Julian calendar, named for Julius Caesar and established in 46 B.C., had accumulated numerous errors. But it wasn't until 1582 that the Vatican Observatory was born with the reform of the Gregorian calendar (named for Pope Gregory XIII) that, based on observation of the stars, established fixed dates for religious festivities.

Consolmagno takes pains to rebut the anti-science image of the Catholic Church. He cites the 19th century Italian priest Angelo Secchi as a pioneer in astronomy and the 20th century Belgian priest Georges Lematre, known as "father of the Big Bang theory," which holds that the universe began in a cataclysmic explosion of a small, primeval superatom.

Astronomical text books in Latin are displayed at the Vatican Observatory. Sylvia Poggioli/NPR hide caption

Astronomical text books in Latin are displayed at the Vatican Observatory.

Run by Jesuits, the Observatory moved to this bucolic setting in the 1930s, when light pollution in Rome obstructed celestial observation.

One domed building in the papal gardens houses a huge telescope dating from 1891. It's called Carte du Ciel map of the sky and it stands under a curved ceiling that slides open. Consolmagno says, "It was one of about 18 identical telescopes that were set up around the world to photograph the sky, and every national observatory was given its own piece of sky to photograph." He adds, it was "one of the first international projects of astronomy."

A native of Detroit, Consolmagno studied physics at the Massachusetts Institute of Technology, volunteered with the Peace Corps in Africa and taught physics before becoming a Jesuit brother in his 40s. He has been at the Observatory for three decades. His passion for astronomy started with a childhood love of science fiction.

"I love the kind of science fiction that gives you that sense of wonder, that reminds you at the end of the day why we dream of being able to go into space," Consolmagno says.

A passionate Star Wars fan, he tells this reporter proudly, "even Obi-Wan Kenobi came to visit" the Observatory, pointing to the signature of actor Alec Guinness, who played the role in the original movie trilogy, in a visitor's book from 1958.

Top scientists teach at the Observatory's summer school. And scientists and space industry leaders have come for a United Nations-sponsored conference on the ethics and peaceful uses of outer space. It cooperates with NASA on several space missions and it operates a modern telescope in partnership with the University of Arizona.

Left: A visitors' book signed by actor Alec Guinness in 1958. Right: A photo of a prelate decades ago reclining to view the telescope. Sylvia Poggioli/NPR hide caption

Left: A visitors' book signed by actor Alec Guinness in 1958. Right: A photo of a prelate decades ago reclining to view the telescope.

"But where we still need to work is with the rest of the world," says the Observatory director, "the people in the pews, especially nowadays. There are too many people in the pews who think you have to choose between science and faith."

To reach those people, the Observatory recently launched a new website and podcasts exploring issues such as meteorites hitting the Earth or how to live on the moon.

And an online store sells merch hoodies, caps, tote bags and posters of the Milky Way.

In just a few months, says the director, visitors to the website have doubled.

As to how the faith-versus-science culture wars can be resolved, Consolmagno says what's most important is that he wears a collar he is a devoutly religious person who also considers himself an "orthodox scientist." "That fact alone shatters the stereotypes," he says.

Another American at the Observatory shattering stereotypes is Brother Robert Macke, curator of the collection of meteorites rocks formed in the early days of the solar system.

Holding a dark rock a few inches long, he says it was formed 4.5 billion years ago providing clues on how the solar system was formed.

"In order to understand the natural world," he says, "you have to study the natural world. You cannot just simply close your eyes and ignore it or pretend that it is other than it is. You have to study it and you have to come to appreciate it."

Consolmagno asked how the study of the stars interacts with his faith says astronomy doesn't provide answers to theological questions, and scripture doesn't explain science. "But the astronomy is the place where I interact with the Creator of the universe, where God sets up the puzzles and we have a lot of fun solving them together," the director says.

And he believes the recent dark period of the pandemic has weakened the arguments of those who are skeptical of science.

"Because people can see science in action, science doesn't have all the answers," he says. "And yet science is still with all of its mistakes and with all of its stumbling is still better than no science."

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The Vatican's Space Observatory Wants To See Stars And Faith Align - NPR

Galactic mergers like those that formed the Milky Way are violent, high-energy events that can be difficult to study. But these collisions determine the shape and composition of galaxies and trigger the formation of stars and new black holes, so untangling how they play out helps scientists understand the forces that shape the universe.

A recent analysis of a super-bright region of the sky 800 million light years from Earth reveals a merger involving three different types of galaxies, including two that likely contain supermassive black holes called active galactic nuclei (AGN).

This new finding was led by University of Maryland astronomy graduate student Jonathan Williams, who is scheduled to present the analysis of this three-galaxy system today at the 238th meeting of the American Astronomical Society.

In addition to providing insight into what happens when galaxies collide, the finding provides a rare glimpse into a merger involving at least one, and possibly two, AGN. In recent years, astronomers have been able to observe black hole mergers with increasing frequency. But most often, such observations have involved smaller black holes, not the supermassive AGN found at the center of galaxies.

This find can reveal details about how active galaxies might be triggered and serve as a guide to understanding how supermassive black holes might come together and merge, said UMD Astronomy Professor Richard Mushotzky, a co-author of the study.

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UMD Astronomer Spots Triple Galaxy Merger That Sheds Light on Black Hole, Galaxy Formation - Maryland Today

For the first time astronomers have observed waves of magnetic energy, known as Alfvn waves, in the photosphere of the sun. This discovery may help explain why the solar corona is so much hotter than the surface.

The sun is made of plasma, and like any plasma it should support Alfvn waves. These are waves in a plasma where the ions move in response to tension from a magnetic field. First predicted over 50 years ago, astronomers had until now had been unable to see them in the sun. But recent observations of the suns photosphere the lowest layer of its atmosphere and the region that releases the light that we can see have finally found them.

Magnetic fields in the sun can bundle together, forming long structures called flux tubes. These flux tubes can drive the formation of Alfvn waves. A team of researchers, led by Dr. Marco Stangalini at Italian Space Agency (ASI,Italy) with scientists from seven other research institutes and universities, including Queen Marys Dr. David Tsiklauri and Ph.D. student Callum Boocock, used the European Space Agencys IBIS to carefully monitor the suns photosphere.

Despite previous claims, Alfvn waves had never conclusively been found on the sun before.

The researchers validated their observations with the aid of magnetohydrodynamic (MHD) simulations, which are computer simulations of the complex plasma physics operating at the suns surface.

Callum Boocock, a Ph.D. student at Queen Marys School of Physics and Astronomy, said: The observations of torsional Alfven waves made by Marco and his team were remarkably similar to the behavior seen in our MHD simulations, demonstrating the importance of these simulations for discovering and explaining wave generation mechanisms.

The finding provides a crucial step to understanding why the outer solar atmosphere, the corona, has a temperature a million degrees hotter than the surface. Something much be transporting energy from the photosphere to the corona, and these Alfvn waves may be the culprit.

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Astronomers Confirm the Existence of Magnetic Waves in the Suns Photosphere - Universe Today

It doesn't happen too often, but sometimes I'll see a press release and/or read a paper reporting a first-of-its-kind observation that genuinely surprises me because I figured it would've been done long ago.

Going through some old emails, though, I saw a press release from a few years ago announcing astronomers had found the first lone neutron star outside our Milky Way galaxy.

My reaction was confusion. Neutron stars are the leftover cores of stars that explode as supernovae; the core collapses down to a ball about 25 kilometers wide, with ridiculously fierce surface gravity (a hundred million times Earth's at least) and intense magnetic fields.

We know of several neutron stars in other galaxies, I thought. They're powerful beasts, and easily capable of blasting out radiation on a scale that could be detected across near intergalactic space. We won't be seeing them in distant galaxies, but there are lots of galaxies pretty close by where we see them.

Then I thought about it for a moment and realized my mistake. First of all this one is alone in space; when a neutron star is orbiting another star like the Sun it can emit powerful X-rays basically announcing its presence to everyone within a million light years. But this one is alone, not orbiting another star.

Second, even from a couple of hundred thousand light years away a lone neutron star isn't terribly bright, so finding one can be hard. Heck, we've been looking for one leftover from Supernova 1987A for over 30 years and still haven't clearly found it.

Sometimes, though, nature makes it easy: This new one was literally circled by a ring of light in the sky.

The Small Magellanic Cloud is a satellite galaxy to the Milky Way, about 200,000 light years from us. In it is a well-known supernova remnant the expanding debris from a massive star exploding called 1E 0102.2-7219. The star probably blew up a thousand or so years ago, sending several times the mass of the Sun worth of gas screaming away from it at thousands of kilometers per second. I first heard of it in 1999 when a Chandra X-ray Observatory image of it came out, which tickled me because it looks just like a giant letter Q in the sky.

That was another reason this news surprised me: The supernova had been known for a long time, so if there were a neutron star in it I figured it would've been seen. But that's not the case.

Astronomers observed this debris with the MUSE camera on the Very Large Telescope in Chile, and saw a small ring of gas near the center. This ring is glowing in visible light (the kind we see) emitted by atoms of oxygen, carbon, and neon, and weirdly is not moving as rapidly as the debris around it; it's expanding but at the relatively pokey rate of about 90 km/sec.

That's weird. But the fact that it's a ring and expanding slowly does strongly imply that the center of the ring is the location of the star that exploded; it's hard to imagine any other way the ring could exist. So they searched archived images of the debris to look for anything left behind by the explosion. It wasn't seen at first in those earlier Chandra observations, but when they reprocessed that old Chandra data they found a sharp X-ray emitting source right smack dab in the center: a neutron star.

Cool. They looked at a fairly narrow range of X-ray colors, but even then the neutron star is blasting out radiation equal to the total energy of the Sun! Think of it this way: Imagine a star so powerful that just in, say, a very narrow slice of red it was emitting as much light as the Sun did across the spectrum. That's the case here, but it's in X-rays, which implies a powerful source of energy. Normal stars are not terribly bright in X-rays, but neutron stars certainly can be.

So there you go: The first lone neutron star ever seen outside our own galaxy.

But we're not done. What the heck was the ring they saw?

The astronomers speculate a bit on what could have formed it. The most likely scenario, they think, is that it comes from deep inside the star that exploded, where there was a very precarious balance. The core of the star collapsed to form the neutron star, and the material above was blasted away at a decent fraction of the speed of light. But material just above the core could have been blown outward, but not nearly as rapidly as material closer to the surface. Caught between gas moving away and gas collapsing down, it expanded slowly well, quickly enough to get from the Earth to the Moon in an hour, but that's still far less than the other debris creating a torus of material around the neutron star.

Given the ring's size and speed, this implies the explosion happened about 7,000 years ago, which is much longer ago than the estimated age of the supernova. However, both numbers have large uncertainties so it's not out of the question the ring formed at the same time the star exploded.

But it's not clear this is actually how the ring formed, so more observations and more models will have to be made.

In astronomy, data are never wasted. Especially now; we can save digital observations that can be used years or even decades later, reprocessed using new techniques, and uncover treasures buried all that time. That was the key to this discovery.

This is the first lone neutron star found outside our galaxy, and finding them is harder than I thought. I may have been surprised by this first one, but now I think finding more is inevitable.

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The first lone neutron star ever seen outside the Milky Way - SYFY WIRE

In 1935 Dundee was given a view across the night sky like no other when Mills Observatory was finally opened after the development was stalled for over 20 years.

Following yesterdays solar eclipse it seemed like the perfect opportunity to dive in to the history of the UKs first purpose-built public astronomical observatory, complete with a papier-mch dome that has withstood eight decades on Balgay Hill.

The observatory wouldnt be what it is today without Dundonian John Mills. A linen and twine manufacturer by day, Mills was a keen astronomer by night and even created his own private observatory on the slopes of the Law, near what is now Adelaide Place.

Mills was also a member of the church and was heavily inspired by Reverend Thomas Dick who was a philosopher as well as author of a number of books on Astronomy and Christian Philosophy.

The reverend was keen to show that science and religion could go hand in hand, believing that the greatness of God could best be appreciated by the study of astronomy, to which he devoted his life to. He also advocated that each and every city should have public parks, public libraries and of course a public observatory.

Although John Mills passed away in 1889 but wanted to ensure Dundee would continue his astronomical work, leaving a bequest to Dundee Town Council with the terms of building an observatory in the city.

After the town council received the bequest they were unsure how exactly they would be able to fulfil Mills wishes as they had no experience of a bequest of its nature.

Hoping they could help, the council decided to offer the money to the Dundee University College in the hope that they would be able to fulfil its terms.

Seeking expert opinions from the likes of the Royal Greenwich Observatory, regarding the feasibility of such a project, the advice they received didnt paint a positive picture and it was thought that only very limited public access would be possible so the College declined the money, deciding that the project didnt fit in to their plans.

A Trust was then set up within the Town Council, and plans began to build the observatory on the summit of the Law.

As the plans were created the outbreak of the First World War in 1914 put the whole project on pause.

Not only could they not continue with the construction but the intended site was instead reserved for the War Memorial, which was erected after the end of the war.

It wouldnt be until the early 1930s that the team were back to the drawing board and with the great Depression came the idea that the observatory would bring much needed work for the local construction industry.

Scotlands Astronomer Royal, Professor Ralph Samson, was brought in as a consultant for the project and he would prove to be a fantastic asset.

Following examinations of several sites he came down strongly in favour of Balgay Hill as being by far the most suitable, both for its astronomical suitability and also for public access. With the site looking on to the river estuary and the sky protected from the main lights of the city by trees providing a purer atmosphere.

Professor Sampson collaborated alongside city architect James MacLellan Brown to design a much more modern building than the one originally planned before the war.

They decided on a sandstone structure with the blocks quarried from Leoch, near Rosemill.

One of the buildings most unique features is not the seven metre dome itself but more what the dome is made of papier-mch.

Despite other observatories featuring the unique construction material, Mills Observatory is the only one still to have the dome in place to this day although it has been restored with waterproofing materials at least twice in its history.

The dome was built by Grubb Parsons and is hand-operated with a steel framework.

The Observatory was formally opened by Professor Sampson on 28 October 1935, and presented to the Town Council by Mr Milne of the Mills Trust in the presence of Lord Provost Buist.

A message of congratulations was sent by the Astronomer Royal at Greenwich, Sir H Spencer Jones.

The original telescope given by the Mills Trust was an 18-inch Newtonian reflector by Grubb Parsons and was electrically driven. The remains of the original telescope can be seen in the upper display area of the Observatory.

By early 1951 Mills Observatory was home to a 19-inch pilot model however although it was described as the first of its kind in the world it unfortunately was purely for photographic work and so not as useful for the amateur public to use.

In February 1951 it was suggested that the pilot telescope be transferred to St Andrews University Observatory and the Mills Observatory would then receive the 10-inch Cooke refracting telescope formerly used as a student training instrument in exchange.

At first the Town Council refused.

Professor W.H.M. Greaves, had succeeded Professor Sampson as Astronomer Royal for Scotland, and was called upon to advise on the matter. In view of the scientific benefits of the move, and lack of interest shown by University College Dundee, he recommended that the transfer take place.

This was done at the universitys expense, and on the understanding that the two telescopes were on mutual loan. The 10-inch refractor had to be modified slightly to fit the Mills dome, and the dew-cap couldnt safely be used. However, it proved to be a much superior instrument for public viewing than the old Newtonian reflector.

Originally built in 1871 it had been privately owned by Walter Goodacre, president of the British Astronomical Association (BAA), who lived in the village of Four Marks, near Winchester.

The telescope was used there by many famous amateurs involved in the work of the BAA and was always described by them as the excellent 10-inch Cooke refractor. It was particularly good for observing fine lunar and planetary detail and although not designed for photographic work, the lens is so good that, with modern cameras, good photographs can be taken.

The main telescope is now a 16 inch Dobsonian reflector which provides spectacular views of the Moon and planets and breath taking views of deep space objects.

The Observatory now also has a 12 inch Meade Schmidt Cassegrain reflector which is fully computerised and can find 30,000 objects in the sky and a solar telescope which allows viewers to observe the sun safely during the summer months.

The Observatory also acquired a number of smaller telescopes over the years.

Ever since its opening to the public the Observatory has continued to inspire generations and has also led to some out of this world discoveries.

While attending St Andrews University, astronomer Robert H. McNaught was a regular visitor to the Mills Observatory and became a friend of former curator Harry Ford.

In 1990 he discovered two minor planets, 6906 John Mills and 6907 Harry Ford, paying homage to his friend and also the Observatorys name sake.

Harry Ford took up his duties in 1967 and organised a number of exhibitions and Open Days were held at which the work of the local amateurs was exhibited, over the years that followed.

Ford also organised displays of the work of the Observatory and the local Society at the BAAs Exhibition Meetings in London, which excited great interest among the assembled amateurs, and resulted in many of them making a special journey to Dundee during their holidays.

Well known TV and radio personality Dr Patrick Moore, praised the work of the Observatory as being quite unique in his experience. He himself has visited the Observatory on a number of occasions and opened the improved facilities in June 1984.

During his speech at the unveiling, Dr Moore said that in the future, as in the past, the Mills Observatory would play a great part in the furtherance of amateur astronomy in Britain, and inspire some to take up astronomy as a career.

In 2005 the Observatory hosted its very first visit from an Apollo astronaut when David Scott, commander of Apollo 15, visited the city.

Unfortunately the venue remains closed due to Coronavirus restrictions and was unable to be used for the partial solar eclipse on June 10 2021 however the site is no stranger to crowds gathering for a piece of the eclipse action.

There wasnt too much room in the Observatory in May 1984 as locals hoped to catch a glimpse of the upcoming eclipse from the dome.

Below a large crowd utilise all the space the Observatory offers as they eagerly await an eclipse that was due in August 1999.

The observatory hopes to reopen soon with restrictions easing and we are sure it has many more years of inspiring Dundonians young and old to come.

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Out of this world: How Mills Observatory was nearly built on Dundee Law - The Courier