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How Researchers Produce Sharp Images of a Black Hole – Universe Today

In April of 2019, the Event Horizon Telescope collaboration history made history when it released the first image of a black hole ever taken. This accomplishment was decades in the making and triggered an international media circus. The picture was the result of a technique known as interferometry, where observatories across the world combined light from their telescopes to create a composite image.

This image showed what astrophysicists have predicted for a long time, that extreme gravitational bending causes photons to fall in around the event horizon, contributing to the bright rings that surround them. Last week, on March 18th, a team of researchers from the Harvard-Smithsonian Center for Astrophysics (CfA) announced new research that shows how black hole images could reveal an intricate substructure within them.

The study that describes their findings, titled Universal interferometric signatures of a black holes photon ring, recently appeared in the journal Science Advances. The team was led by Michael Johnson, an astrophysicist with the CfA, and induced members from Harvards Black Hole Initiative (BHI), Los Alamos National Laboratory, Princeton Center for Theoretical Science, and multiple universities.

As Johnson explained in a recent CfA press release:

The image of a black hole actually contains a nested series of rings. Each successive ring has about the same diameter but becomes increasingly sharper because its light orbited the black hole more times before reaching the observer. With the current EHT image, weve caught just a glimpse of the full complexity that should emerge in the image of any black hole.

As the law of General Relativity tells us, gravitational fields alter the curvature of spacetime. In the case of a black hole, the effect is extreme and causes even light (photons) to infall around them. These photons cast a shadow on the bright ring of infalling gas and dust that is accelerated to relativistic speeds by the black holes gravity.

Around this shadowed region is a photon ring produced from photons that are concentrated by the strong gravity near the black hole. This ring can tell astronomers a lot about a black holes since its size and shape reveal the mass and rotation (aka. spin) of the black hole. Because of the EHT images, black hole researchers now have a tool with which to study black holes.

Since the 1950s, astronomers have learned a great deal about them by studying the effect they have on their surrounding environment. In other words, the study of black holes has been indirect and theoretical in nature. But with the ability to take images of these celestial objects, astronomers can finally study them directly and glean real data.

George Wong, a physics graduate student at the University of Illinois at Urbana-Champaign, was responsible for developing software to produce simulated black hole images. This software is what allowed for images that were of the highest resolution to date to be computed and allowed their team to decompose them into the predicted series of sub-images. As Wong indicated:

Bringing together experts from different fields enabled us to really connect a theoretical understanding of the photon ring to what is possible with observation. What started as classic pencil-and-paper calculations prompted us to push our simulations to new limits.

What was especially surprising to the researchers, however, was how the substructure revealed by the black hole image creates new opportunities for research. While the subrings they revealed are normally invisible to the naked eye on images, they produce very clear signals when observed by arrays of telescopes using interferometry.

This presents astronomers with a relatively easy way to expand on the work conducted by the EHT collaboration thus far. While capturing black hole images normally requires many distributed telescopes, the subrings are perfect to study using only two telescopes that are very far apart, said Johnson. Adding one space telescope to the EHT would be enough.

The fields of astronomy and astrophysics have experienced multiple revolutions in recent years. Between the first-ever observations of interstellar objects, the confirmation of gravitational waves, and the first direct observations of a black hole. These firsts have enabled research that promises to unlock a number of enduring mysteries about the cosmos.

The teams research was made possible in part by grants issued by NASA, the National Science Foundation (NSF), the Department of Energy (DoE), and multiple scientific and research foundations.

Further Reading: CfA

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How Researchers Produce Sharp Images of a Black Hole - Universe Today

Infinite Visions Were Hiding in the First Black Hole Images Rings – The New York Times

A year ago a team of radio astronomers startled the world with the first photograph of a black hole, lurking like the eye of Sauron in the heart of a distant galaxy. Now it appears there was more hiding in that image than we had imagined.

When you point a telescope at a black hole, it turns out you dont just see the swirling sizzling doughnut of doom formed by matter falling in. You can also see the whole universe. Light from an infinite array of distant stars and galaxies can wrap around the black hole like ribbons around a maypole, again and again before coming back to your eye, or your telescope.

The image of a black hole actually contains a nested series of rings, said Michael Johnson of the Harvard-Smithsonian Center for Astrophysics, not unlike the rings that form around your bathtub drain.

Dr. Johnson was lead author of a study, describing the proposed method that would allow our telescopes to pry more secrets from the maw of any black hole, that was published in the March 18 edition of the journal Science Advances.

He and other authors of the paper are also members of the team operating the Event Horizon Telescope, a globe-girding network of radio telescopes that made that first image of a black hole. Their telescope saw these rings, but it didnt have enough resolution to distinguish them, so they were blurred into a single feature.

The work, scientists with the project said, pointed toward new ways to shed light, so to speak, on the properties of black holes, particularly by adding a radio telescope in space to the existing E.H.T. network.

This paper is, in my professional capacity, very cool! Shep Doeleman, also of Harvard-Smithsonian and leader of the E.H.T. collaboration, said in an email.

Andrew Strominger, a Harvard theorist and co-author of the paper, said, Understanding the intricate details of this historic experimental observation has forced theorists like myself to think about black holes in a new way.

Einstein thought that was crazy, but astronomers have found that space is littered with these apocalyptic creatures. There seems to be a supermassive black hole, weighing millions or billions of times more than the Sun, lurking in the center of every galaxy.

The Event Horizon Telescope, named after the edge, the point of no return from a black hole, consisted of eight radio observatories on six mountains and four continents. All that observing power was yoked together by a technique called very-long baseline interferometry, to achieve the resolution of a telescope as big as the Earth. For 10 days in April 2017 they pointed it at the center of the giant galaxy M87 in the Virgo constellation, where there is a black hole as massive as six billion Suns belching tongues of radio fire.

The resultant image of gases heated to billions of degrees swirling around the cosmic drain matched the predictions of Einsteins theory, as far as anyone can tell. A copy of the telescopes vision now resides in the permanent photography collection of the Museum of Modern Art in New York.

But the Event Horizons work has barely begun, Dr. Doeleman said. For one thing the scientists are trying to make a movie of the supermassive black hole in the center of our own Milky Way galaxy; a summertime attempt was recently called off because of the coronavirus pandemic.

If they could increase the size of their event horizon network by adding an antenna in space, Dr. Doeleman said, they could gain enough resolution to see individual photon rings, as they are called, turning the event horizon into a true cosmic laboratory for testing our most fundamental theories.

As Peter Galison of Harvard, another E.H.T. collaborator said, As we peer into these rings, we are looking at light from all over the visible universe, we are seeing farther and farther into the past, a movie, so to speak, of the history of the visible universe.

Dr. Johnson said there were several space radio telescopes on the drawing boards that could fit the bill. One is a Russian mission called Millimetron, which is optimistically hoping to launch in 2029. Another is the Origins Space Telescope, which has been proposed to NASA for a launch in 2035.

Dr. Johnson said astronomers dont know the mass of the M87 black hole they revealed last year to better than 10 percent accuracy, nor do they know if and how fast it is spinning. A space mission with a radio antenna would allow them to see the ring structure and determine the M87s mass to an accuracy of a fraction of a percent, and could estimate its spin.

All this if Einstein was right, he added. Other theories of gravity and other types of compact objects (wormholes, naked singularities, boson stars) would suggest a very different ring structure.

So this is a way of studying exactly what lies at the centers of galaxies, in a way that we can never learn from larger scale measurements such as the orbits of stars or gas, Dr. Johnson said.

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Infinite Visions Were Hiding in the First Black Hole Images Rings - The New York Times

April’s full moon is a supermoon, and rises on the 7th – Brainerd Dispatch

But this closeness doesnt last. The very next day, it will be obvious that Saturn has moved away from Mars. In fact, both Saturn and Jupiter are heading westward, away from the red planet. On the 9th, Saturn will be almost exactly midway between Mars, to the left, and Jupiter. By months end, the gap between Mars and Saturn will have opened to nearly 20 degrees.

While Saturn and Jupiter are pulling away from Mars, Earth is moving closer. During April the distance to Mars drops from 135 million miles to 114 million miles. Also, Jupiter is slowly drifting closer to Saturn. In December these two planets make a very close pass.

In the evening sky, Venus visits the lovely Pleiades star cluster. On the 1st, the cluster hovers close above the queen of planets. The next night, Venus has arrived at the border, and on the 3rd the planet appears to be another star in the cluster. On the 4th, Venus is above the Pleiades, and from then on the two objects rapidly separate. The one wrinkle is the bright waxing moon that shines those nights, so keep your binoculars handy.

And if that werent enough, Aprils full moon is one of the closer ones this year and qualifies as a supermoon. It rises the evening of the 7th, looking not only bigger and brighter than usual, but very round because itll be only a couple of hours or so from the moment of perfect fullness. Also, have a look on the 25th, when a young crescent moon of the next cycle appears below Venus and next to Aldebaran, the eye of Taurus, the bull.

April ends with an astronomically based holiday that the ancient Celts (and many contemporary ones) called Beltane. It was celebrated on May 1, which began formally at sundown April 30 and was one of four cross-quarter days falling midway between an equinox and a solstice. The night of April 30 was when evil spirits that had been wreaking havoc since Halloweenanother cross-quarter dayhad a last fling. At dawn on May 1, they had to begin their annual six-month exile from the world of humans. Beltane was, and is, a celebration of the coming summer and hopes for an abundant harvest.

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The University of Minnesota offers public viewings of the night sky at its Duluth and Twin Cities campuses. For more information and viewing schedules, see:

Duluth, Marshall W. Alworth Planetarium: http://www.d.umn.edu/planet

Twin Cities, Minnesota Institute for Astrophysics: http://www.astro.umn.edu/outreach/pubnight

Check out the astronomy programs at the University of Minnesota's Bell Museum Exploradome: http://www.bellmuseum.umn.edu/education/exploradome

Find U of M astronomers and links to the world of astronomy at http://www.astro.umn.edu

8/22/19 Contact: Deane Morrison, University Relations, (612) 624-2346, morri029@umn.edu

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Minnesota Starwatch is a service of the Minnesota Institute for Astrophysics, located in the Tate Laboratory of Physics and Astronomy, 116 Church St. S.E., Minneapolis MN 55455.

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April's full moon is a supermoon, and rises on the 7th - Brainerd Dispatch

New mission would provide a road map in the search for alien atmospheres – CU Boulder Today

A new spacecraft proposed by scientists at CU Boulder could soon be NASAs nose in space, sniffing out the environments beyond Earths solar system that might host planets with thick atmospheres.

Astrophysicist Kevin France is leading the development of that mission, called the Extreme-ultraviolet Stellar Characterization for Atmospheric Physics and Evolution (ESCAPE). Hes hoping it will provide the critical reconnaissance work in humanitys search for life far away from home.

NASA and the entire astronomical community have made the search for signs of life on exoplanets a priority, said France, an assistant professor in the Laboratory for Atmospheric and Space Physics (LASP) and the Department of Astrophysical and Planetary Sciences (APS). We believe that detectable life outside the solar system probably relies on the presence of an atmosphere.

This month, the space agency gave him and his colleagues an important go-ahead to start the hunt for habitable environments: ESCAPE will be one of two candidates vying to be the next satellite to launch under NASAs ambitious Explorers Program.

A concept design for theExtreme-ultraviolet Stellar Characterization for Atmospheric Physics and Evolution (ESCAPE) spacecraft in an alien star system. (Credit: Brandy Coons/Laura Murray/CU Boulder)

If selected, the mission, which would have a budget of no more than $145 million, could pack a lot of scientific punch for the cost.

These promising proposals under the Explorers Program bring out some of the most creative, innovative ways to help uncover the secrets of the universe," said Thomas Zurbuchen, associate administrator of NASAs Science Mission Directorate, in a statement. "From studying stars and planets outside our solar system to seeking answers to the largest cosmic mysteries, I look forward to the breakthrough science from these modest size missions.

The proposed mission, a joint effort of LASP, JILA and the Center for Astrophysics and Space Astronomy (CASA) at CU Boulder, wouldnt seek out exoplanet atmospheres directly. Instead, ESCAPE would take a close look at distant stars.

Allison Youngblood, a research scientist at LASP, explained that some stars probably dont make good homes for habitable planets. In particular, stars that spit out a lot of high-energy radiationin this case, extreme ultraviolet lightcan strip the atmospheres away from orbiting worlds. Think of it like a strong gust blowing through a pile of leaves.

This high-energy radiation is absorbed in the highest layers of a planet's atmosphere and regulates the escape of an atmosphere to space, said Youngblood, part of Frances ESCAPE team. We must measure the extreme ultraviolet radiation from exoplanet host stars to be able to say whether or not exoplanets can hang on to their atmospheres.

Over the course of its proposed two-year mission, which could begin in 2025, ESCAPE would survey the radiation streaming from more than 200 stars.

By doing that, France hopes to narrow down the list of the spots where scientists might expect to find the signals of flourishing life.

Were going to be able to make a road map of the most promising habitable worlds that NASA will spend its resources studying over the next 20 years, France said.

For now, he and his colleagues are buckling down. NASA has given the team $2 million dollars to develop their concept for ESCAPE further, and the agency will make its final decision in 2021.

The teams vision is definitely ambitious, France said. ESCAPE would measure about 7-feet-long and weigh more than 300 poundsa roughly Shaquille ONeal-sized chunk of machinery in low-Earth orbit.

ESCAPE also makes use of a new type of telescope designone that would be capable of measuring the faint extreme-ultraviolet radiation from distant stars, data that astronomers have so far not been able to collect.

Over the next nine months, were going to be making and testing engineering models of some of the more critical parts of the system in order to demonstrate that our design is actually going to perform as well as we think its going to, said Brian Fleming, a research professor at LASP and the instrument scientist for ESCAPE.

In other words, the researchers have some busy months ahead of them.

We were extremely excited when we found out we were selected, France said. Then maybe a day later it hit us that, Oh my gosh, we actually have to do all this. Its very gratifying to see it all come together and for NASA to be excited about it.

Other CU Boulder members of the ESCAPE team include Zachory Berta-Thompson and Adam Kowalski, assistant professors in APS; James Green, a professor in APS; and Jeffrey Linksy of JILA; and James Mason and Nick Kruczek, research scientists at LASP. Tom Patton leads the projects engineering team at LASP.

The effort also brings together researchers from the Ball Aerospace, Southwest Research Institute, and the National Solar Observatory, based in Boulder. ESCAPE also has science and technical partners at NASAs Marshall Space Flight Center and numerous other universities and science institutions around the world.

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New mission would provide a road map in the search for alien atmospheres - CU Boulder Today

Pollution down, sky clearer: Amateur astronomers have a good time – Hindustan Times

Amateur astronomers in cities across India are making the best out of a bad situation to observe celestial objects --stars, constellations and planets -- in skies that have become unusually clear because of reduced pollution after the all-India lockdown came into force on March 25 to stop the spread of the coronavirus (Covid-19).

The night skies, especially, have brightened with many more stars visible, according to astrophysicists in Kolkata who are monitoring celestial events with a telescope.

The stars, which were earlier only eight times brighter compared to the black sky in the background, have become at least 13 times brighter now compared to the black background. With the help of our telescopes we can now observe stars which were at least three times fainter earlier, said Sandip K Chakrabarti, director of Indian Centre for Space Physics (ICSP) and former head of the astrophysics and cosmology department at the SN Bose National Centre for Basic Sciences.

HT reported on March 24a general improvement in air quality across the world amid lockdowns to check the spread of Covid-19. The European Space Agency (ESA) has released satellite images showing a plunge in nitrogen dioxide (NO2) levels. In India, the government has cancelled flights and trains and taken public transport off the roads.

Constellations such as the Orion, Auriga, Gemini and Canis Minor have become much brighter now. One can see these constellations much clearly because of the drop in air pollution levels, said Basudev Bhattacharya, president ofthe Sky Watchers Association in Kolkata.

The concentration of aerosols that used to scatter light and create a dense haze have dropped because of the lockdown. An analysis by the Centre for Science and Environment in Delhi has revealed that morning and evening peaks in PM 2.5 (particulate matter 2.5, fine, respirable pollution particles) levels have flattened out.

As a result of this, several stars and planets have become much brighter. The Canopus star in the southern hemisphere is looking quite bright. Planets such as Jupiter, Mars and Saturn have become brighter and can be seen before dawn around 4 am. Venus is also looking brighter in the evening sky, said J Khemchandani, secretary of Ahmedabads astronomy club.

The sky is now dotted with stars, many of which were earlier not visible. Earlier, only two objects from the deep sky were visible. But now I can see at least five including the Little Beehive star cluster, Messier 36, Messier 37 and Messier 38. These could be seen in the western sky in the evening. Earlier I could see only two to three stars of the Scorpio constellation. But now I can see the entire constellation. Even the pole star is shining brightly over the last one week or so, said Sneh Kesari, an amateur astronomer in Delhi.

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Pollution down, sky clearer: Amateur astronomers have a good time - Hindustan Times

Mystery of Supermassive Black Holes Shortly After the Big Bang Explanation Discovered – SciTechDaily

According to classical theories, these space giants would not have had the time to develop in the young Universe. Yet, observations say they were already present. A new study by SISSA proposes a response to the fascinating question. Credit: NASA/JPL-Caltech

These space giants would not have had the time to develop in the young Universe. Yet, observations say they were already present; a new study proposes a response to the mystery.

They are billions of times larger than our Sun: how is it possible that, as recently observed, supermassive black holes were already present when the Universe, now 14 billion years old, was just 800 million years old? For astrophysicists, the formation of these cosmic monsters in such a short time is a real scientific headache, which raises important questions on the current knowledge of the development of these celestial bodies. A recent article published in The Astrophysical Journal, by the SISSA Ph.D. student Lumen Boco and his supervisor Andrea Lapi, offers a possible explanation to the thorny issue. Thanks to an original model theorized by the scientists from Trieste, the study proposes a very fast formation process in the initial phases of the development of the supermassive black holes, those up to now considered slower. Proving, mathematically, that their existence was possible in the young Universe, the results of the research reconcile the timing required for their growth with the limits imposed by the age of the Cosmos. The validity of the theory can be fully validated thanks to future gravitational wave detectors namely Einstein Telescope and LISA, but tested in several basic aspects also with the current Advanced LIGO/Virgo system.

The scientists started their study with a piece of well-known observational evidence: the growth of supermassive black holes occurs in the central regions of galaxies, progenitors of the current elliptical galaxies, which had a very high gas content and in which the stellar formation was extremely intense. The biggest stars live a short time and very quickly evolve into stellar black holes, as large as several scores of solar masses; they are small, but many form in these galaxies. The dense gas that surrounds them, explain Boco and Lapi, has a very powerful definitive effect of dynamic friction and causes them to migrate very quickly to the center of the galaxy. The majority of the numerous black holes that reach the central regions merge, creating the supermassive black hole seed. Boco and Lapi continue: According to classical theories, a supermassive black hole grows at the center of a galaxy capturing the surrounding matter, principally gas, growing it on itself and finally devouring it at a rhythm which is proportional to its mass. For this reason, during the initial phases of its development, when the mass of the black hole is small, the growth is very slow. To the extent that, according to the calculations, to reach the mass observed, billions of times that of the Sun, a very long time would be required, even greater than the age of the young Universe. Their study, however, showed that things could go much faster than that.

Our numerical calculations show that the process of dynamic migration and fusion of stellar black holes can make the supermassive black hole seed reach a mass of between 10,000 and 100,000 times that of the Sun in just 50-100 million years. At this point, the researchers say, the growth of the central black hole according to the aforementioned direct accretion of gas, envisaged by the standard theory, will become very fast, because the quantity of gas it will succeed in attracting and absorbing will become immense, and predominant on the process we propose. Nevertheless, precisely the fact of starting from such a big seed as envisaged by our mechanism speeds up the global growth of the supermassive black hole and allows its formation, also in the Young Universe. In short, in light of this theory, we can state that 800 million years after the Big Bang the supermassive black holes could already populate the Cosmos.

The article, besides illustrating the model and demonstrating its efficacy, also proposes a method for testing it: The fusion of numerous stellar black holes with the seed of the supermassive black hole at the center will produce gravitational waves which we expect to see and study with current and future detectors, explain the researchers. In particular, the gravitational waves emitted in the initial phases, when the central black hole seed is still small, will be identifiable by the current detectors like Advanced LIGO/Virgo and fully characterizable by the future Einstein Telescope. The subsequent development phases of the supermassive black hole could be investigated thanks to the future detector LISA, which will be launched in space around 2034. In this way, explain Boco and Lapi, the process we propose can be validated in its different phases, in a complementary way, by future gravitational wave detectors.

This research concludes Andrea Lapi, coordinator of the Astrophysics and Cosmology group of SISSA, shows how the students and researchers of our group are fully approaching the new frontier of gravitational waves and multi-messenger astronomy. In particular, our main goal will be to develop theoretical models, like that devised in this case, which serve to capitalize on the information originating from the experiments of current and future gravitational waves, thereby hopefully providing solutions for unresolved issues connected with astrophysics, cosmology, and fundamental physics.

Reference: Growth of Supermassive Black Hole Seeds in ETG Star-forming Progenitors: Multiple Merging of Stellar Compact Remnants via Gaseous Dynamical Friction and Gravitational-wave Emission by L. Boco, A. Lapi and L. Danese, 9 March 2020, The Astrophysical Journal.DOI: 10.3847/1538-4357/ab7446

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Mystery of Supermassive Black Holes Shortly After the Big Bang Explanation Discovered - SciTechDaily

Texas Tech Prof. Would Reconsider Atheism if Donald Trump Dies of Chinese Virus – Breitbart

Texas Tech University Professor Richard Wigmans told his colleagues in an email last week that he might reconsider his atheism if President Donald Trump died after contracting the Wuhan coronavirus.

According to a report by Campus Reform, Texas Tech Professor Richard Wigmans has come under fire this week for an email he sent to faculty members in which he suggested that he would reconsider his lack of faith in God if President Trump contracted the Wuhan coronavirus and died.

Wigmans, who focuses his researchesparticle physics, astrophysics, and cosmology, is referred to on his faculty profile as the worlds foremost expert on calorimetry for particle physics experiments. Calorimetry refers to the measurement of the amount of heat that is released or absorbed during a chemical reaction.

I am personally an atheist, but if #45 would die as a result of this virus, I might reconsider, Wigmans wrote in the email.

In a short comment to Campus Reform, Wigmans claimed that his email is being misinterpreted.This is a statement about myself, not about someone elseI have distributed some emails to my colleagues in which I provide a scientists perspective on the available COVID-19 data, and use the observed trends to make some predictions.

When asked directly if he hoped that President Trump would die from the virus, Wigmans blurred the line further. I have not expressed such a wish, he said.

Skyler Wachsmann, chairman of Young Conservatives of Texas at Texas Tech, condemned Wigmans for his distasteful remark.Implying that the President would enjoy for supporters of political opponents and for the elderly to suffer from this virus is disgusting, as is his comment expressing hope that President Trump would die from the Coronavirus, Wachsmann said.

Stay tuned to Breitbart News for more updates on this story.

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Texas Tech Prof. Would Reconsider Atheism if Donald Trump Dies of Chinese Virus - Breitbart

Educational Shows For Kids to Stream From Home – Den of Geek UK

So youre in quarantine, and youve got kids playing too much Roblox while the school system scrambles to put digital learning in place. Even for families with experience educating at home, it can be a daunting task coming up with learning experiences to fill a students day, especially with most public libraries closed during the COVID-19 crisis. While television is not the cure-all for the problem, a nice educational program, perhaps one that includes instructional materials, could be just the thing to fill in the instructional gaps and give flustered parents a little break from playing teacher.

Weve listed here our favorite educational television program in each of the main subject areas: math, science, language arts, and social studies. Most of these are available via PBS and are often presented along with materials for follow-up lessons. Theres obviously a lot more out there for the elementary set than any other age group, but we tried to include programming that could appeal to a wide variety of grade levels broken down by subject.

In the opening credits of Genius by Stephen Hawking, the titular physicist says, I believe that anyone can answer big questions for themselves. This show takes the questions we all ask such as Can We Time Travel? and Where Did the Universe Come From? and turns them into the episode titles designed specifically to explore those ideas through practical demonstrations, commentary from experts, and the interaction of three so-called regular people that act as the audiences proxy. The large-scale experiments and incredible stunts will appeal to students of many ages as they come to grips with molecular biology, astrophysics, and even Hawkings speciality, quantum mechanics.

Genius by Stephen Hawking was produced in 2016 but is currently available to stream through your PBS station and is free to Amazon Prime subscribers.

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Educational Shows For Kids to Stream From Home - Den of Geek UK

Universities Space Research Association’s Adam Goldstein Named Co-Investigator on NASA’s Recently Elected Proposed Mission on LargE Area burst…

COLUMBIA, Md. and WASHINGTON, March 25, 2020 /PRNewswire/ -- NASAScience Mission Directorate recently selected four Small Explorer (SMEX) mission concepts that would study cosmic explosions and the debris they leave behind, as well as monitor how nearby stellar flares may affect the atmospheres of orbiting planets. Among these is the LargE Area burst Polarimeter (LEAP) concept led by Principal Investigator Mark McConnell at the University of New Hampshire in Durham and Director of R&D at the Southwest Research Institute.The mission is being managed by NASA's Marshall Space Flight Center. One of the Co-Investigators on the project is Adam Goldstein of Universities Space Research Association (USRA) Science and Technology Institute in Huntsville, Alabama.

"These promising proposals under the Explorers Program bring out some of the most creative, innovative ways to help uncover the secrets of the universe," said Thomas Zurbuchen, associate administrator of the agency's Science Mission Directorate in Washington. "From studying stars and planets outside our solar system to seeking answers to the largest cosmic mysteries, I look forward to the breakthrough science from these modest size missions."

The LargE Area Polarimeter (LEAP) mission would be an instrument mounted as an external payload to the International Space Station, and its primary mission is to study the polarization of gamma rays from gamma-ray bursts (GRBs). GRBs are the most energetic explosions in the universe and are highly-relativistic jets of material ejected from the core-collapse of massive stars or when two neutron stars collide. An instrument capable of measuring the polarization of the GRB radiation has been long-desired in the community, since it could answer several open questions about the jet physics and the underlying processes that produce the jets. Specifically, measuring the polarization could inform us about the magnetic field strengths present in these systems during core-collapse or collision; it could tell whether the jet itself mostly contains matter moving at very near the speed of light or contains a lot of radiation; and it could also indicate how the matter in the jet is converted to the gamma-rays that we observe.

USRA's Adam Goldstein stated, "LEAP is an exciting project to be involved in because it promises to advance the study of GRBs and our understanding of high-energy astrophysics.GRBs have been studied for several decades, and yet there are still many open questions about their exact nature.LEAP could help answer a number of those."

Mark McConnell, the Principal Investigator, stated, "LEAP represents the culmination of many years of work to make some extremely important measurements. Not only do we have the right instrument for the task, but we also have been very successful in putting together a team of researchers who represent some of the foremost researchers in the study of Gamma Ray Bursts. We are thrilled with the prospects for the LEAP project."

The LEAP instrument is composed of gamma-ray scintillators coupled to photo-multiplier tubes, together creating detectors that owe heritage to both the current Fermi Gamma-ray Burst Monitor (GBM) and the previous Burst and Transient Source Experiment (BATSE) onboard the Compton Gamma-ray Observatory. Unlike GBM and BATSE, however, LEAP's unique arrangement of the detectors will allow it to measure the polarization of the gamma-rays that neither of the previous instrument had the capability to observe. Additionally, its very large observing area, several times that of GBM, will make it sensitive to detecting many GRBs, so GRB polarization could be measured for potentially hundreds of GRBs, allowing for a population analysis.

The selected missions are provided an opportunity to improve their proposed mission concept during an extended phase-A -- until 2021. NASA intends to select two of the four proposed mission concepts at that time for further development and launch in 2025.

Ghassem Asrar, Senior Vice President of Science at USRA noted, "We are thrilled to see USRA scientists supporting one of proposed SMEX mission concepts.What is also special about the LEAP Mission of Opportunity as an attached payload is that it will take full advantage of the International Space Station."LEAP will also complement NASA's Imaging X-ray Polarimetry Explorer (IXPE), scheduled to launch in 2021.

USRA, in partnership with Marshall Space Flight Center will take part in the awarded concept study to develop a final report on the ability of LEAP to achieve its proposed science. It is expected that in 2021, NASA will select the final mission concepts, and if LEAP is one of the missions chosen, it will be built and is expected to be operational in 2025.

About USRAFounded in 1969, under the auspices of the National Academy of Sciences at the request of the U.S. Government, the Universities Space Research Association (USRA) is a nonprofit corporation chartered to advance space-related science, technology and engineering. USRA operates scientific institutes and facilities, and conducts other major research and educational programs, under Federal funding. USRA engages the university community and employs in-house scientific leadership, innovative research and development, and project management expertise. More information about USRA is available at http://www.usra.edu.

About the Explorers ProgramManaged by Goddard, this is the oldest continuous NASA program designed to provide frequent, low-cost access to space using principal investigator-led space science investigations relevant to the Science Mission Directorate's astrophysics and heliophysics programs. Since the launch in 1958 of Explorer 1, which discovered Earth's radiation belts, the Explorers Program has launched more than 90 missions, including the Uhuruand Cosmic Background Explorer (COBE)missions that led to Nobel Prizes for their investigators. For information about the Explorers Program visit: https://explorers.gsfc.nasa.gov/index.html

PR Contact:Suraiya Farukhi, Ph.D.sfarukhi@usra.edu443-812-6945

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Universities Space Research Association's Adam Goldstein Named Co-Investigator on NASA's Recently Elected Proposed Mission on LargE Area burst...

How Researchers Produce Sharp Images of a Black Hole – Universe Today

In April of 2019, the Event Horizon Telescope collaboration history made history when it released the first image of a black hole ever taken. This accomplishment was decades in the making and triggered an international media circus. The picture was the result of a technique known as interferometry, where observatories across the world combined light from their telescopes to create a composite image.

This image showed what astrophysicists have predicted for a long time, that extreme gravitational bending causes photons to fall in around the event horizon, contributing to the bright rings that surround them. Last week, on March 18th, a team of researchers from the Harvard-Smithsonian Center for Astrophysics (CfA) announced new research that shows how black hole images could reveal an intricate substructure within them.

The study that describes their findings, titled Universal interferometric signatures of a black holes photon ring, recently appeared in the journal Science Advances. The team was led by Michael Johnson, an astrophysicist with the CfA, and induced members from Harvards Black Hole Initiative (BHI), Los Alamos National Laboratory, Princeton Center for Theoretical Science, and multiple universities.

As Johnson explained in a recent CfA press release:

The image of a black hole actually contains a nested series of rings. Each successive ring has about the same diameter but becomes increasingly sharper because its light orbited the black hole more times before reaching the observer. With the current EHT image, weve caught just a glimpse of the full complexity that should emerge in the image of any black hole.

As the law of General Relativity tells us, gravitational fields alter the curvature of spacetime. In the case of a black hole, the effect is extreme and causes even light (photons) to infall around them. These photons cast a shadow on the bright ring of infalling gas and dust that is accelerated to relativistic speeds by the black holes gravity.

Around this shadowed region is a photon ring produced from photons that are concentrated by the strong gravity near the black hole. This ring can tell astronomers a lot about a black holes since its size and shape reveal the mass and rotation (aka. spin) of the black hole. Because of the EHT images, black hole researchers now have a tool with which to study black holes.

Since the 1950s, astronomers have learned a great deal about them by studying the effect they have on their surrounding environment. In other words, the study of black holes has been indirect and theoretical in nature. But with the ability to take images of these celestial objects, astronomers can finally study them directly and glean real data.

George Wong, a physics graduate student at the University of Illinois at Urbana-Champaign, was responsible for developing software to produce simulated black hole images. This software is what allowed for images that were of the highest resolution to date to be computed and allowed their team to decompose them into the predicted series of sub-images. As Wong indicated:

Bringing together experts from different fields enabled us to really connect a theoretical understanding of the photon ring to what is possible with observation. What started as classic pencil-and-paper calculations prompted us to push our simulations to new limits.

What was especially surprising to the researchers, however, was how the substructure revealed by the black hole image creates new opportunities for research. While the subrings they revealed are normally invisible to the naked eye on images, they produce very clear signals when observed by arrays of telescopes using interferometry.

This presents astronomers with a relatively easy way to expand on the work conducted by the EHT collaboration thus far. While capturing black hole images normally requires many distributed telescopes, the subrings are perfect to study using only two telescopes that are very far apart, said Johnson. Adding one space telescope to the EHT would be enough.

The fields of astronomy and astrophysics have experienced multiple revolutions in recent years. Between the first-ever observations of interstellar objects, the confirmation of gravitational waves, and the first direct observations of a black hole. These firsts have enabled research that promises to unlock a number of enduring mysteries about the cosmos.

The teams research was made possible in part by grants issued by NASA, the National Science Foundation (NSF), the Department of Energy (DoE), and multiple scientific and research foundations.

Further Reading: CfA

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How Researchers Produce Sharp Images of a Black Hole - Universe Today

The Mystery of Supermassive Black Hole Formation – AZoQuantum

Written by AZoQuantumMar 24 2020

Supermassive black holes are billions of times bigger than the Sun, but how is this possible? According to recent observations, these space giants already existed when the Universe was just 800 million years old and is currently 14 billion years old.

The emergence of these celestial giants in such a brief time poses a real scientific dilemma to astrophysicists, raising significant questions on the present knowledge relating to the formation of these cosmic bodies.

A new article, authored by Scuola Internazionale Superiore di Studi Avanzati (SISSA) PhD student Lumen Boco and his supervisor Andrea Lapi and recently published in The Astrophysical Journal, provides a potential explanation to this tricky problem.

Based on an original model conceptualized by Trieste researchers, the study recommends an extremely rapid formation process during the preliminary phases of the formation of the giant black holes, which, so far, were believed to be slower.

The study results mathematically showed that supermassive black holes could possibly exist in the young Universe and reconciled the timing needed for their development with the limitations imposed by the Cosmos age.

Thanks to upcoming gravitational wave detectors such as LISA and Einstein Telescope, the validity of this concept can be completely confirmed, while this was also tested in a number of rudimentary aspects using the present Advanced LIGO/Virgo system.

The researchers began their analysis with a piece of familiar observational proofthe development of giant black holes that takes place in the core regions of galaxies, progenitors of the present elliptical galaxies, which had an extremely high concentration gas and in which the star formation was very strong.

The biggest stars live a short time and very quickly evolve into stellar black holes, as large as several scores of solar masses; they are small, but many form in these galaxies, stated Boco and Lapi.

The duo further explained that the thick gas surrounding the black holes has a very strong definitive effect of dynamic friction and makes them to move quite rapidly to the core of the galaxy. Most of the various black holes that approach the core regions combine and produce the giant black hole seed.

According to classical theories, a supermassive black hole grows at the centre of a galaxy capturing the surrounding matter, principally gas, growing it on itself and finally devouring it at a rhythm which is proportional to its mass.

Lumen Boco, PhD Student, and Andrea Lapi, Supervisor and Coordinator, The Astrophysics and Cosmology Group, SISSA

Boco and Lapi continued, For this reason, during the initial phases of its development, when the mass of the black hole is small, the growth is very slow. To the extent that, according to the calculations, to reach the mass observed, billions of times that of the Sun, a very long time would be required, even greater than the age of the young Universe.

But the researchers study revealed that things could go relatively faster than that.

Our numerical calculations show that the process of dynamic migration and fusion of stellar black holes can make the supermassive black hole seed reach a mass of between 10,000 and 100,000 times that of the Sun in just 50-100 million years, added the researchers.

At this juncture, the scientists stated that the growth of the central black hole according to the aforementioned direct accretion of gas, envisaged by the standard theory, will become very fast, because the quantity of gas it will succeed in attracting and absorbing will become immense, and predominant on the process we propose.

Nevertheless, precisely the fact of starting from such a big seed as envisaged by our mechanism speeds up the global growth of the supermassive black hole and allows its formation, also in the Young Universe. In short, in light of this theory, we can state that 800 million years after the Big Bang the supermassive black holes could already populate the Cosmos.

Lumen Boco, PhD Student, and Andrea Lapi, Supervisor and Coordinator, The Astrophysics and Cosmology Group, SISSA

The study, apart from describing the model and illustrating its efficacy, also suggests a way for testing it: The fusion of numerous stellar black holes with the seed of the supermassive black hole at the centre will produce gravitational waves which we expect to see and study with current and future detectors, the scientists explained.

Specifically, the gravitational waves released in the preliminary phaseswhen the central black hole seed is still smallcan be identified using the existing detectors such as Advanced LIGO/Virgo and fully definable by the upcoming Einstein Telescope.

The resultant development phases of the giant black hole can possibly be analyzed due to the upcoming detector LISA, which will be introduced in space around 2034.

In this manner, the process we propose can be validated in its different phases, in a complementary way, by future gravitational wave detectors, explained Boco and Lapi.

This research shows how the students and researchers of our group are fully approaching the new frontier of gravitational waves and multi-messenger astronomy. In particular, our main goal will be to develop theoretical models, like that devised in this case, which serve to capitalise on the information originating from the experiments of current and future gravitational waves, thereby hopefully providing solutions for unresolved issues connected with astrophysics, cosmology and fundamental physics.

Andrea Lapi, Supervisor and Coordinator, The Astrophysics and Cosmology Group, SISSA

Source: https://www.sissa.it/

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The Mystery of Supermassive Black Hole Formation - AZoQuantum

The true impact of SpaceXs Starlink constellation on astronomy is coming into focus – The Verge

Ever since SpaceX launched its first batch of internet-beaming satellites last year, astronomers have watched with dread as the company continued to blast more spacecraft into orbit. Could this ballooning constellation of bright satellites fill the night sky with artificial light and muck up observations of the Universe for years to come? Now, new data is partially validating what many astronomers have feared since that first launch.

Up until now, people have been somewhat in the dark about the true impact of SpaceXs internet-from-space project called Starlink, which envisions nearly 12,000 of these satellites orbiting Earth. SpaceXs satellites are super bright compared to others, and astronomers have been worried that with so many luminous satellites in the sky, the odds of one passing in front of a telescope and obscuring an image will increase.

It turns out, some astronomers have reason to be concerned. Certain types of astronomy may be more negatively affected than others, one peer-reviewed study shows, particularly those kinds that scour large swaths of the sky over long periods of time looking for faint, faraway objects. That means scientists looking for distant objects beyond Neptune including the hunt for the mysterious Planet Nine might have trouble when Starlink is complete. Additionally, Starlink may be much more visible during twilight hours, or the first few hours of the night, which could be a major problem in the hunt for massive asteroids headed toward Earth. It depends on what science youre doing, and thats really what it comes down to, Jonathan McDowell, an astrophysicist at Harvard and spaceflight expert who wrote the study accepted by Astrophysical Journal Letters, tells The Verge.

Meanwhile, scientists are also learning if SpaceXs effort to mitigate the brightness of its satellites is actually going to work. The company coated one of its satellites in an attempt to make it appear less visible in the sky. Now, the first observations of that satellite are being published, and the coating is working but it might not be enough to make everyone happy. It doesnt solve the issue, Jeremy Tregloan-Reed, a researcher at the University of Antofagasta and lead author on the study, which is undergoing peer review at Astronomy and Astrophysics Letters, tells The Verge. But it shows that SpaceX has taken on board astronomers concerns, and it does appear to be trying to solve the situation.

For astronomers, light is everything. Observing celestial objects in different wavelengths of light is the best method we have for exploring the Universe. Thats why adding artificial light to the sky freaks out so many scientists. Some astronomers take long-exposure images of the sky, gathering as much light as possible from distant objects and when a bright satellite reflecting light from the Sun passes overhead, it can leave a long white streak that ruins the picture.

Of course, the sky is a big canvas, and one tiny satellite isnt going to be a major headache. A host of factors dictate exactly how and when satellites will be a problem. A satellites size, shape, height, and path around Earth all affect exactly how much light it reflects from the Sun and where people will see it the most. Meanwhile, the time of year and the time of night determine how much sunlight is shining on a satellite at any given moment.

To figure out Starlinks exact impression on the night, McDowell made a comprehensive simulation based on what we know about where all of the Starlink satellites are going. Ahead of launching its constellation, SpaceX had to file multiple requests with the Federal Communications Commission, detailing where the company planned to send all of its spacecraft. Using that information, McDowell came up with a snapshot of which areas will see the most satellites overhead and what times of night will be the worst for observations.

In the more northern and southern latitudes, Starlink satellites will dominate the horizon during the first and last few hours of the night. In the summertime, itll be much worse, with hundreds of satellites visible for those in rural areas away from city light pollution. Where I live in [Boston], I can see the planes hovering over Logan [Airport] on the horizon, says McDowell. Thats what it will look like, but itll be satellites and itll be a lot of them. SpaceX declined to comment for this story.

While people living in cities and towns wont really notice, this spells bad news for those hunting really distant faint objects using long exposures. The longer that you have the shutter open for, the more that youre likely to have an observation impeded by one of these streaks that are quite bright, Michele Bannister, a planetary astronomer at the University of Canterbury in New Zealand who helped McDowell with his research, tells The Verge. That means those hunting Planet Nine and objects at the edge of the Solar System have some cause for alarm.

Additionally, asteroid hunters are going to be extra affected by this constellation, says McDowell. Theyre really hosed, because they need to look at twilight, he says. Scientists looking for asteroids orbiting near Earth often look for these objects near the Sun; they observe just after sunset when they can see the part of the sky near the Sun thats too bright to see during the day. Thats where the problem with illuminated Starlink satellites is the worst, he says. Even from regular 30-degree latitude observatories, theyre going to have serious problems.

As for what that means for these astronomy fields, one obvious concern is that a potentially hazardous asteroid could go unnoticed until its too late to act appropriately. Its also possible observers will have to take expensive countermeasures to get the kinds of images they want. It may mean you have to observe twice as long, if you have to throw away half your data, says McDowell. So thats expensive. Or you may need to make changes to your telescope design, to stop reflections from a satellite.

The silver lining here, at least, is that McDowells study found that Starlink may not really have a big effect on a lot of other astronomers work, especially those who only look at small slices of the night sky for certain periods of time. But his work does fly in the face of what SpaceX CEO Elon Musk has said about Starlink and its astronomy repercussions. I am confident that we will not cause any impact whatsoever in astronomical discoveries. Zero, Musk said during a space conference at the beginning of March. Thats my prediction. And well take corrective action if its above zero.

Despite Musks brazen proclamation, the truth is SpaceX has already taken some corrective action, but new research shows it may not be enough to silence all of the companys critics.

On its third Starlink launch in January, SpaceX included a satellite that had been painted with an experimental coating, meant to darken the spacecrafts reflectivity. Nicknamed DarkSat, the spacecraft has been of particular interest to amateur satellite trackers. Various observatories have taken images of DarkSat as its passed overhead to gauge just how much fainter it appears compared to its cohort.

The answer, it seems, is that DarkSat is indeed darker but only slightly. Once it reached its final orbit, the satellite appeared 55 percent fainter compared to another bright Starlink satellite, according to Tregloan-Reeds study. Thats based on the initial observations he made using a telescope at the Ckoirama Observatory in Chile. The DarkSat coating does push the satellite beyond being able to be seen with the naked eye, says Tregloan-Reed.

Thats a big reduction, but 55 percent may not be enough for some observatories. The Vera Rubin Observatory in Chile is still under construction, but it has the massive task of surveying the entire night sky. Its going to be able to give us the history of the Solar system in absolutely intricate and amazing detail, says Bannister of the survey. And I think thats definitely something that is under threat. People at the observatory have estimated that the Starlink satellites would need to be even fainter than DarkSat in order to truly stay out of the way and not saturate the images gathered.

The good news is that SpaceX has hinted that more extreme countermeasures may be on their way. During its latest launch, a SpaceX employee noted that while the coated satellite showed a notable reduction in brightness, a future Starlink satellite may be equipped with a sunshade to further reduce reflectivity. We have a couple other ideas that we think could reduce the reflectivity even further, the most promising being a sunshade that would operate in the same way as a patio umbrella, or a sun visor but for the satellite, Jessica Anderson, a lead manufacturing engineer at SpaceX, said during the live stream.

Tregloan-Reed says hes hopeful about some kind of shade. If that was to work then in theory it would block out the sunlight completely, he says.

Still, that doesnt solve every single astronomy problem because even a darkened satellite can still be a nuisance. Astronomers searching for planets beyond our Solar System, for instance, often take very sensitive measurements of distant stars, looking for dips in their brightness that might indicate a foreign planet passing by. If a satellite, even a dark one, were to pass in front of a star someone was observing, it could throw off the search for these alien worlds.

No matter what, it seems that a giant constellation is going to have some kind of negative impact on someone it cant be helped. And looking at the big picture, SpaceX isnt alone in its attempt to create a mega-constellation of satellites. The company just gets the most attention because its proposing the largest number of spacecraft, and its vehicles are big, bright, and lower in the sky compared to other proposed constellations. Others like OneWeb and Amazon want to also fill the sky with internet-beaming vehicles.

Such a large influx of artificial bright spots is really the heart of the issue. I understand the importance of Starlink; I can see the benefits of worldwide internet, says Tregloan-Reed. Its just the sheer numbers that are worrying me.

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The true impact of SpaceXs Starlink constellation on astronomy is coming into focus - The Verge

Mobile astronomy: Put the Milky Way in your pocket with ‘Our Galaxy’ smartphone app – Space.com

From time to time at star parties, I encountered someone who isn't very impressed with the dim, fuzzy object I'm showing them through my telescope. But once I explain what the object is, how far away it is, and how it connects to our place in the galaxy and the wider universe beyond, it sparks their imagination and they look at it again with renewed interest and appreciation. A new fun and educational app called Our Galaxy will let anyone learn about our place in the cosmos, and feel that sense of wonder.

In addition to the obvious bright planets and stars, the night sky is sprinkled with star clusters, nebulas, and distant galaxies, many of which are revealed by looking through binoculars and backyard telescopes. Astronomers refer to those exotic objects as deep-sky objects. Their positions in the sky aren't completely random. Star clusters and nebulas populate the spiral arms of our home galaxy, the Milky Way with more of them occurring closer to the center of the galaxy and fewer of them appearing along its outer rim. Their locations in the sky allow astronomers to trace out the structure and dimensions of our galaxy, and to determine where new stars are being formed within it.

Related: Stunning photos of our Milky Way Galaxy (gallery)

Planetary nebulas are the corpses of stars not unlike our sun that reached the end of their lives. Those objects can appear anywhere in our sky because our sun sits within a 3-dimensional volume of space; surrounded by stars of all ages. Globular clusters are spherical, densely-packed collections of old stars that orbit our galaxy like bees around a hive so they tend to be found near the band of the Milky Way, but not inside it. Distant galaxies are sprinkled throughout the sky, but they can only be mapped and observed where our own galaxy's gas and dust don't block their distant light.

Bill Tschumy, one of the creators of the popular SkySafari app, has created the perfect tool to understand our place in the Universe. The Our Galaxy app for iOS and MacOS lets users visualize the locations and physical properties of deep-sky objects within and around our galaxy. The app is a relatively small download at less than 60 Mb. Once loaded on your iPhone, it puts a deep sky expert in your pocket and the larger display on an iPad really shows off its wealth of detailed imagery.

The Our Galaxy app can be operated in two modes that are enabled by tapping Galaxy or Sky on the app's toolbar. The toolbar also features icons to open the search menu and Views library, read a page of information about the selected object, toggle red-light night mode, open the app's settings menu and help. Two whimsical spaceship-shaped icons in the toolbar serve as zoom controls one flies you closer, the other flies you out.

Galaxy View presents a 3-dimensional model of our Milky Way's barred spiral form that you can tilt and rotate, and zoom in and out of. A single tap in the Settings Orientation menu lets you select preset orientations, such as an edge-on view and a face-on view. In the Center menu, you can choose to keep our sun in the center, or rotate around the galactic core or around a selected star or deep-sky object. Across the top of the screen are shown your distance from the selected object, and the field of view (FOV) being displayed in light-years.

Sky View draws a rectangular (orthographic) map of the entire sky as viewed from Earth. Sky coordinates in degrees are labelled around the perimeter of the map. The major stars and lines that form the constellations are plotted in white on a black background. The deep-sky objects are overlain using colored symbols. The map can be enlarged and panned around. Tapping a symbol shows its object's name. Plotting one or more categories of deep-sky objects on the map view illustrate how they can be used to define our galaxy's structure, or be completely independent of it all useful information for understanding how galaxies like ours are structured. A single tap switches between sky and galaxy view.

The app is highly configurable. You can decide whether to display labelled names next to the symbols, identify the various spiral arms of the galaxy, and show the Constellation Sectors the portions of the Milky Way that lie in the direction of certain constellations, such as Orion, Gemini or Cygnus.

To clean up the view, simply enter the settings menu and tap the remove options.

The app contains an extensive library of stars and objects. An object can be selected by typing its name or its designation into the search menu or by tapping its symbol on the screen. Multiple deep-sky objects can be displayed at the same time, as I describe below.

The app's powerful search menu allows you to type all or a portion of an object's name or designation, include or exclude object types, and limit the search to specific ranges of magnitude (brightness), distance, age, size and more. You can even search all constellations, or select a single constellation.

The list of results can then be displayed on the map or 3D model. It's especially interesting to see how the stars and deep-sky objects of a single constellation fall at vastly different distances from our sun.

The more you work with the app, the more you will learn about astronomy, astrophysics, and cosmology all presented using clear, understandable text and graphics.

The Views library is especially educational for understanding how various classes of objects populate the galaxy. Nine categories are offered: individual stars and OB Associations (hot, bright stars), open and globular clusters, various types of nebulas, galaxies, and our galaxy's structural components. There is also an entry for the list of well-known Messier objects. Each entry has an information icon to summon a description of that object class.

Tapping any category opens a sublist that allows you to select all members of the class, or sub-groups. For example, in the Diffuse Nebulae view, you can treat emission and reflection nebulas as separate groups, or combined, each type color-coded appropriately (with red for light emitted from hydrogen, blue for starlight scattered off dust, and green for both phenomena).

The Visibility menu contains sliders to plot galactic axes and to add wire mesh representations of the galaxy's central bulge, dark matter halo sphere, and more.

For cosmology buffs, the app contains 3D locations for hundreds of galaxies. Selecting the galaxy category and using "Galaxy view" puts you 92 billion light-years away from home. Manipulating the model shows how some galaxies concentrate in groups while others leave empty voids in the visible universe.

The Our Galaxy app will give you a true perspective on our place in space. Bill Tschumy has posted a YouTube video demonstration of the app here. Enjoy exploring the galaxy and, as always, keep looking up!

Chris Vaughan is an astronomy public outreach and education specialist at AstroGeo, a member of the Royal Astronomical Society of Canada, and an operator of the historic 74-inch (1.88-meter) David Dunlap Observatory telescope. You can reach him via email, and follow him on Twitter @astrogeoguy, as well as on Facebook and Tumblr. Follow SkySafari on Twitter @SkySafariAstro. Follow us on Twitter @Spacedotcom and on Facebook.

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Mobile astronomy: Put the Milky Way in your pocket with 'Our Galaxy' smartphone app - Space.com

An Interview With Matthew Mercer About The Explorers Guide To Wildemount – Forbes

The crossover effort between Dungeons & Dragons and Critical Role is here,

Matthew Mercer and his show Critical Role has a profound impact on Dungeons & Dragons. Millions of new players have tried D&D after watching Mercer and his crew of nerdy voice actors play through an epic story. The Critical Role crew have played live shows across the world and Mercer has been Dungeon Master for notable people from Vin Diesel to Stephen Colbert. They have also expanded beyond livestreaming content into shows for Amazon Prime. This month, Matt Mercer gets to cross another item off his bucket list; author of an official D&D book from Wizards of the Coast called Explorers Guide to Wildemount.

I was caught off guard because Wizards contacted us, said Mercer, I had been brought in to contribute on a couple books which was a really, really cool experience, but I never expected it at this level. I had done one book with Green Ronin, the TalDorei guide which was an awesome learning experience, a time consuming experience where I learned a lot through that process with them. If it wasnt with Wizards in an opportunity like this I probably would have held off because of how crazy life has been.

The book details the continent of Wildemount on the world of Exandria where the campaigns of Critical Role are set. Wildemount is the setting of the current episodes on the show. The book includes details on the setting, spells, character options and plenty of information fans of the show are looking to devour.

Ever since I finished [the TalDorei guide] my world building and note taking had taken more of a formal approach, said Mercer, so, thankfully when this came around, I had more thorough notes and ideas that didnt completely need an overhaul. Of course, I only developed enough to touch on the campaign that I was running. The process from that point became How do I take the things that I already have established or partially fleshed out into an entirely suitable form? and What ideas do I have beyond those and how do I flesh them out in an equally exciting way?

Even D&D fans who are not deep into the show will find some interesting ideas contained within. The Heroic Chronicle charts offer players a way to pull together a character with backstories that link their characters together and to the setting without wandering through a few awkward sessions of getting to know characters. Mercers world also offers some unusual magic schools that draw their power from scientific sources such as gravity, time and probability.

A lot of that stems from a love of quantum physics and astrophysics growing up, said Mercer, Ive always had a love of those weird esoteric elements of theoretical science. I came up with the Kyrn Dynasty before we started the second campaign as a way to renovate the class and present these ideas in an innovative way in a classic D&D setting. As part of that religious scenario, I thought about what kind of magic in the world hadnt really been touched on and what magic intrigued me. I wanted to look at how gravity and probably affects you from a theoretically standpoint. How could I adapt that under an umbrella of magic that was unique to this world?

Mercer took a hand in every element of the book from story elements to mechanical write ups. He was joined by veteran D&D authors James J. Haeck, James Introcaso and Chris Lockey with development handled by Jeremy Crawford, Dan Dillon, Ben Petrisor and Kate Welch.

I began doing some home brewed class mechanic stuff on DMs Guild years ago and found that I really enjoyed it, said Mercer. Getting better at it as time goes on has been a real thrill for me. Being able to write narrative world building elements is a safer space because nobody can argue with it. With player facing mechanics theres a much more intense level of scrutiny, so its a bigger challenge to create. I really enjoy monster design because I make a lot of monsters for Critical Role because we have such a large party of powerful players. Its become a secondary hobby of mine to create weird, interesting, dynamic battles for my players.

Explorers Guide to Wildemount is available on Amazon or from Friendly Local Game Stores around the world.

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An Interview With Matthew Mercer About The Explorers Guide To Wildemount - Forbes

Scientists Made an Explanation of Why Time Cannot Be Reversed – Somag News

Scientists from Portugal conducted a study on the problem of not returning to the same starting point in running n-body simulations backwards. The researchers found that in the n-body simulation with three objects, the time symmetry was disrupted.

Most laws of physics do not care about moving time backwards or forwards in theoretical studies. The laws of physics work the same way, whether time is moved forward or backward. This is called time symmetry. However, when we come to the real universe, things are different.

A team of scientists, led by Tjarda Boekholt from the University of Aveiro in Portugal, observed that three objects acting with each others gravity distorted the symmetry of time, albeit for a very short moment.

In the article in which the study is explained, The quantitative relationship between the chaos in star dynamics systems and the irreversibility of time has been uncertain until now. In this study, we examine chaotic three-body systems in free fall, using the correct and precise n-body code Brutus, which goes beyond the standard double precision arithmetic.

The N-body problem is one of the famous problems of astrophysics. N-body problem occurs when more objects are added to a system that interacts with the gravitational effect. To explain the N-body problem, we can look at a simple example of Newtonian physics.

According to Newtons laws of motion and Newtons law of gravitation, the movements of two bodies moving in orbit around a central point can be mathematically estimated. However, when another object is added to the system, things become difficult. Objects begin to distort each others trajectories under the influence of gravity and add an element of chaos to the system. This interaction with Newtonian physics or general relativity theory cannot be fully explained under a single formula.

We can only estimate the movement of the Solar System, which we understand many features very well, for only a few million years. Chaos does not allow to guess more. Therefore, scientists think that chaos in the universe is not a mistake, but a feature.

Scientists can also run the simulation backwards when they create n-body simulations. However, the backwards-operated simulation never returns to its original starting point. The uncertainty that the simulation does not return to its original starting point is due to a problem in simulation or chaos, so far it has not been known.

Tjarda Boekholt and his team from Aveiro University prepared a new test to eliminate this uncertainty. Simon Portegies Zwart from Boekholt and Leiden University had written an n-body simulation code called Brutus to prevent numerical computational errors in such operations. Scientists used Brutus to test the time symmetry of a system with three objects.

The three objects in the simulation that scientists test are black holes. These black holes were tested in two separate simulation scenarios. In the first scenario, before one of the three black holes was expelled from the system, all black holes moved in each others complex trajectories. In the second scenario, the simulation was run backwards by moving from the end point of the first scenario.

When both tests were done, scientists found that simulation could not be undone in 5 percent of the trials. The researchers determined that this was due to a difference in value as small as the Plack constant.

Tjarda Boekholt said, The movement of the three black holes has shown that even something as small as the Plancks constant can cause a chaotic result to affect the movements. The size of the Planck constant has an exponential effect and breaks the time symmetry.

5 percent may not seem like a very large proportion. However, since it would not be known which of the simulations would be within five percent, the researchers concluded that n-body simulations were basically unpredictable.

In this way, they made sure that the problem was not caused by a problem in the simulations that the n-object simulations did not return to the original starting point when the run was run backwards.

Being unable to turn back time is not just a mathematical argument anymore, it is something hidden in the basic laws of nature, said researcher Simon Portegies Zwart. Three-body systems made up of planets or black holes can never escape the advancement of time.

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Scientists Made an Explanation of Why Time Cannot Be Reversed - Somag News

Birmingham scientist recognised with international physics prize – University of Birmingham

A University of Birmingham physicist has been awarded a prestigious prize for his contributions to gravitational wave research.

Dr Davide Gerosa, an early career researcher in the Universitys School of Physics and Astronomy, was recognised by the International Society on General Relativity and Gravitation in their 2020 awards.

He receives the Societys flagship Young Scientist Prize, awarded only to researchers with fewer than 8 years experience working in their field. Nominees for the prize are expected to have displayed significant achievement and exceptional promise for future achievements in relativity and gravitation.

Dr Gerosa was commended for his outstanding contributions to gravitational-wave astrophysics, including new tests of general relativity.

A member of the University of Birminghams Gravitational Waves Institute, Dr Gerosa studies the impact of Einsteins general relativity on the astrophysical world. His particular research interests include astrophysical inference with gravitational-wave sources, black-hole binary spin dynamics, black-hole recoils, accretion disks and tests of general relativity.

This is a truly exciting time for gravitational-wave astronomy, a golden age of discoveries, says Dr Gerosa. Its a huge privilege to be working in this field. I would like to thank all my supervisors and mentors for their invaluable support in these past years - this is their prize as well."

The University of Birmingham is ranked amongst the worlds top 100 institutions. Its work brings people from across the world to Birmingham, including researchers, teachers and more than 6,500 international students from over 150 countries.

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Birmingham scientist recognised with international physics prize - University of Birmingham

‘Minor planet’ bonanza: 139 new objects discovered beyond Neptune – Space.com

The list of Pluto's neighbors just got considerably longer, potentially boosting scientists' odds of finding the putative Planet Nine.

Astronomers have discovered 139 more "minor planets" small bodies circling the sun that are neither official planets nor comets in the dark, frigid depths beyond Neptune's orbit, a new study reports. The new additions represent nearly 5% of the current trans-Neptunian object (TNO) tally, which stands at about 3,000, the researchers said.

The scientists pored over data gathered by the Dark Energy Survey (DES) during its first four years of operation, from 2013 to 2017. The DES studies the heavens using the 520-megapixel Dark Energy Camera, which is mounted on the Blanco 4-meter telescope at the Cerro Tololo Inter-American Observatory in Chile.

Related: Trans-Neptunian objects in the outer solar system (infographic)

As the project's name implies, the main goal of the DES involves shedding light on dark energy, the mysterious force thought to be behind the universe's accelerating expansion. But the high-resolution DES imagery has a number of other applications, including the discovery of small objects in our own solar system, as the new study shows.

The researchers started out with 7 billion DES-detected dots, which they whittled down to 22 million "transients" after ruling out objects such as galaxies that appeared in roughly the same spot on multiple nights. Those 22 million were further culled to 400 TNO candidates, whose movements the team was able to track over at least six different nights.

After months of vetting by analysis and observation, the team verified 316 of the small bodies as bona fide TNOs. These cataloged objects lie between 30 and 90 astronomical units (AU) from the sun, and 139 of them are new to science, the researchers said. (1 AU is the Earth-sun distance, which is about 93 million miles, or 150 million kilometers.)

The techniques the researchers developed could aid future TNO searches, including those potentially conducted by the Vera C. Rubin Observatory, which is scheduled to come online in the early 2020s, study team members said.

"Many of the programs we've developed can be easily applied to any other large datasets, such as what the Rubin Observatory will produce," lead author Pedro Bernardinelli, a physics and astronomy graduate student at the University of Pennsylvania, said in a statement.

The team members are also now running their analyses on the DES' entire six-year data set, an effort that could yield an additional 500 or so newfound TNOs. (The DES' initial run wrapped up in 2019.) Such new additions could end up being bread crumbs that lead to Planet Nine, the hypothesized world that some scientists think lurks undiscovered in the far outer solar system, hundreds of AU from the sun.

Planet Nine's existence, after all, is inferred from weird clustering in the orbits of certain TNOs.

"There are lots of ideas about giant planets that used to be in the solar system and aren't there anymore, or planets that are far away and massive but too faint for us to have noticed yet," study co-author Gary Bernstein, an astronomy and astrophysics professor at the University of Pennsylvania, said in the same statement.

"Making the catalog is the fun discovery part," Bernstein added. "Then, when you create this resource, you can compare what you did find to what somebody's theory said you should find."

The new study was published this week in The Astrophysical Journal Supplement Series. You can read a preprint of it for free at arXiv.org.

Mike Wall is the author of "Out There" (Grand Central Publishing, 2018; illustrated by Karl Tate), a book about the search for alien life. Follow him on Twitter @michaeldwall. Follow us on Twitter @Spacedotcom or Facebook.

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'Minor planet' bonanza: 139 new objects discovered beyond Neptune - Space.com

Here’s how a massive new telescope will revolutionize our view of the sun – Space.com

It's an image of the sun like nothing anyone has ever seen: glowing, golden kernels divided by dark latticework, like a stained-glass window forged by astrophysics.

But that image, the "first light" data taken by a massive new solar telescope, is only a preview of how the observatory will change the way we see the star that shapes every day of our lives. That "caramel corn" image was stunning to many people, even solar scientists.

The new image was "crystal clear, sharp," said Valentin Martnez Pillet, director of the National Solar Observatory. That institution operates the Daniel K. Inouye Solar Telescope, which was funded by the National Science Foundation and which captured the new data. Martnez Pillet said that, in decades of viewing solar images, he's never seen anything like the new one. "That's as good as it gets," he told Space.com.

Related: Our sun will never look the same again thanks to two solar probes and one giant telescope

"It was always the case where you would look at the solar image and you knew, yeah, we need to do better," Martnez Pillet said. Not anymore.

But although he was awed just like everyone else, he saw the image a little differently than others may have. Many people fixated on the large, pale "kernels," each about the size of Texas. But for Martnez Pillet, the most compelling features in the first-light image were the crackles of granulated brightness nestled between the kernels.

Scientists have never been able to see those granules clearly before, yet they believe the bright dots are key to understanding solar phenomena and how we experience those events way out here in Earth's neighborhood. "As scientists, our eyes went to the brightest tiny, little features," Martnez Pillet said. "The reason for that is we know these are the roots of the solar magnetic field."

The sun's magnetic field dictates precisely how the plasma, or soup of charged particles that make up our star, roils in the sun and blasts out across the solar system. The blasts take different forms, from the slow, steady flow called the solar wind to the massive outbursts called coronal mass ejections. But around Earth, the plasma can cause a host of phenomena called space weather, which can harm astronauts, damage communications and navigation satellites, and cause other disruptions. Scientists want to make better predictions of these events, and to do so, they need to understand how the sun and its magnetic field really work.

Of course, the crackly "first light" image is only one step toward reaching that goal. And the instrument that produced the image is just one of three instruments the solar telescope will use once the facility, located on the Hawaiian island of Maui, is fully operational.

The other two instruments, which should be installed by this summer, will tell scientists much more about the dynamics of the magnetic field than any image could, thanks to two other key techniques. "Everything we do in astronomy is either imaging, spectroscopy or polarimetry," Martnez Pillet said. "We solar astronomers need to do all of them."

Spectroscopy is a standard astronomical technique that analyzes the specific wavelengths of light that a source emits a technique that can reveal the locations of different elements. Spectroscopy can also tell scientists where plasma is moving higher or lower in the sun by using Doppler shifts, the phenomenon that tweaks all light depending on whether its source is moving toward or away from the instrument.

Polarimetry is a less common astronomical technique, because for polarimetry to be successful, scientists need to be able to capture a lot of photons, or light, which is tricky for more distant stars. But the sun is, of course, much closer than any other star, and the Inouye Solar Telescope's polarimeter will be the largest such instrument ever built, making polarimetry a powerful approach for studying the sun's magnetic field, Martnez Pillet said.

In general, Earth's magnetic field is reasonably steady over time and space. North is north is north. The sun's magnetic field, by contrast, is dynamic. "The sun has billions of compasses and magnets moving around, and we need to know the directions of these compasses," Martnez Pillet said. That's what the tiny, bright spots in the new image represent: individual, dynamic magnetic fields.

And although most sunlight doesn't have any sense of direction, the light from these spots does because the magnetic field gives that light direction. Polarimetry measures that direction, and those measurements can give scientists a better understanding of activity in the magnetic field.

With that knowledge, scientists hope to begin tracing space weather phenomena back to their very beginnings on the sun. "We are magnetically connected to the sun," Martnez Pillet said. "There are so many physical processes that we don't know what their origins really are on the sun."

Scientists hope the new solar telescope will give them enough detailed data to begin evaluating the potential origins of different phenomena. "We have theories," Martnez Pillet said. "We need to start saying, 'OK, these are the good theories; these are the ones that are not working.'"

The Inouye Solar Telescope won't be alone in that effort. In particular, it has two crucial partners that are taking instruments directly to the sun: NASA's Parker Solar Probe and the Solar Orbiter, which NASA and the European Space Agency jointly operate. The Parker Solar Probe is flying closer to the surface of the sun than any spacecraft has before, and the Solar Orbiter, which launched last month, will give scientists their first look at the sun's poles.

The Inouye Solar Telescope has company here on Earth as well, Martnez Pillet said. In particular, he pointed to the National Solar Observatory's network of six smaller solar telescopes stationed around the world. Those telescopes, working two at a time as Earth's spin carries each in view of our star, offer a constant look at the whole Earth-facing side of the sun.

With these four projects, scientists hope to understand space weather well enough to predict it reliably. "We're going to need a decade; it's going to be a long process," Martnez Pillet said. "It's exciting times to be a solar astronomer."

Email Meghan Bartels at mbartels@space.com or follow her @meghanbartels. Follow us on Twitter @Spacedotcom and on Facebook.

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Here's how a massive new telescope will revolutionize our view of the sun - Space.com

The universe may have been filled with supermassive black holes at the dawn of time – Livescience.com

Nine hundred million years after the Big Bang, in the epoch of our universe's earliest galaxies, there was already a black hole 1 billion times the size of our sun. That black hole sucked in huge quantities of ionized gas, forming a galactic engine known as a blazar that blasted a superhot jet of bright matter into space. On Earth, we can still detect the light from that explosion more than 12 billion years later.

Astronomers had previously discovered evidence of primeval supermassive black holes in slightly younger "radio-loud active galactic nuclei," or RL AGNs. RL AGNs are galaxies with cores that look extra-bright to radio telescopes, which is considered evidence that they contain supermassive black holes. Blazars are a unique type of RL AGN that spit out two narrow jets of "relativistic" (near-light-speed) matter in opposite directions. Those jets emit narrow beams of light at many different wavelengths and have to be pointed right at Earth for us to detect them across such vast distances. This new blazar discovery moves the date of the oldest confirmed supermassive black hole to within the first billion years of the universe's history and suggests there were other, similar black holes in that era that we haven't detected.

"Thanks to our discovery, we are able to say that in the first billion years of life of the universe, there existed a large number of very massive black holes emitting powerful relativistic jets," Silvia Belladitta, a doctoral student at the Italian National Institute for Astrophysics (INAF) in Milan and co-author of a new paper on the blazar, said in a statement.

Related: Twisted physics: 7 mind-blowing findings

The discovery by Belladitta and her co-authors confirms that blazars existed during an epoch of our universe's history known as "reionization" a period after a long, post-Big Bang dark age when the first stars and galaxies began to form.

And discovering one blazar strongly suggests there were many others, the authors wrote. If only one blazar existed in this early phase of the universe, it would be an extraordinarily lucky break for it to have pointed its narrow, visible beam at Earth. It's much more likely that there were many such blazars pointing in all sorts of directions, and that one of them happened to throw its light our way.

These blazars, the authors wrote, were the seeds of the supermassive black holes that dominate the cores of large galaxies across our universe today including Sagittarius A*, the relatively quiet supermassive black hole at the center of our Milky Way.

"Observing a blazar is extremely important. For every discovered source of this type, we know that there must be 100 similar, but most are oriented differently, and are therefore too weak to be seen directly," Belladitta said.

That information helps astrophysicists reconstruct the story of how and when these monster black holes formed.

Originally published on Live Science.

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The universe may have been filled with supermassive black holes at the dawn of time - Livescience.com

This astrophysicist could become the first non-binary person to lead a major political party in Canada – PinkNews

Amita Kuttner could be the first non-binary person to lead a major political party in Canada. (Amita Kuttner)

A non-binary astrophysicist named Amita Kuttner has announced theyre running to be the next leader of Canadas Green Party.

Kuttner, whos from North Vancouver, is the latest candidate to jump into the race to replace the partys longtime leader, Elizabeth May.

Speaking to Burnaby Now, the 29-year-old, who has a PhD in astronomy and astrophysics from the University of California, said that they are running to be Green Party leader because a large number of people encouraged them to do so.

I fully believe you cannot achieve full equity before you break down the (gender) binary, because along with it goes so many ideas of what gender means, and I think if we just get to a point where people are just people, that is useful, they said.

Kuttner outlined three pillars that their campaign will be based on.

I think the first step is to create safe and inclusive spaces, and politics is tough for that. All the parties have got problems in terms of that, they said, adding the solution goes beyond diversifying the partys candidate list.

You cant just add people and have quotas and then get where you need to go. The work that Ive done on diversity, Ive learned that it really is about the space you create.

The second pillar would be genuinely evidence-based policy, which Kuttner may have an upper edge in with a background as an astrophysicist.

The third (pillar) is making sure that were ready for the future, everything that that brings, in terms of crises and breakthroughs, whether it be technology or a catastrophe, they said, adding they would be applying their scientific lens to developing policies.

We need to make sure that all our policy is driven by really clear values and principles, they said.

Kuttner, who ran as the Green Party for Burnaby North-Seymour in 2019, is one of few non-white candidates in the race to replace May.

It was interesting being in a party that was very white, Kuttner said when they announced their leadership bid, emphasising that the party must do more than increase diversity among its candidates.

Much like with my gender, I get annoyed with labels because I feel like it alienates people. If you say youre a socialist or if you say youre capitalist, people attach assumptions with those words. So I do have an issue with that, they added.

Kuttner also says they want to bring a more evidence-based approach to policy into the Green Party.

We need to make sure we dont have any room for criticism when it comes to credibility on evidence, Kuttner said.

Our official platform has always been science-based. But if we read the policy book, theres stuff that needs ironing out.

If they win the Green Party leadership, Amita Kuttner said they are prepared to move anywhere in Canada in order to get a seat in parliament.

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This astrophysicist could become the first non-binary person to lead a major political party in Canada - PinkNews


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