Shadow of Milky Way’s giant black hole seen for the first time By Daniel Clery, Science Magazine.   Excerpt: After 5 years, astronomers release picture of Sagittarius A*’s event horizon, ringed by bright gas. Astronomers today released the first image of the supermassive black hole at the center of the Milky Way Galaxy—or at least a picture of its shadow. Eight radio observatories around the globe and more than 300 scientists joined forces to image the object known as Sagittarius A* (Sgr A*), a feat thought impossible until just a few years ago. ...The team, known as the Event Horizon Telescope (EHT), in 2019 produced the  first ever image of a black hole , at the center of the nearby giant galaxy M87. The M87 black hole is 1600 times more massive than Sgr A*. Yet the similarity of the two images—bright rings of gas trapped in death spirals around these ultimate sinkholes—shows how Albert Einstein’s theory of gravity, general relativity, works the same at all scales.… See also

Catch a failing star: the tense wait for a supernova By Robin McKie , The Guardian.  Excerpt: ...When a supernova erupts, it sprays the cosmos with heavy elements – so observing one nearby would provide precious information about the creation of matter in our galaxy. ...Scientists estimate that on average about 20 supernovae occur in a galaxy such as ours every thousand years. Yet only  five have been observed in the last millennium . East Asian and Arabic records indicate there were supernovae in 1006, 1054 and 1181, while European documents recall ones that occurred in 1572 and 1604. ...if supernovae are so brilliant, why have we only detected five in the past 1,000 years? Why have we not seen a number that is nearer the 20 suggested by observations of other galaxies? The answer is straightforward, says Sullivan. “Our galaxy is like a flat plate and our solar system is about two-thirds of the way towards its edge. A supernova that occurs

Discovery Alert: A Flood of New Planets, Plus Hint of an ‘Exomoon' By Pat Brennan, NASA's Exoplanet Exploration Program.  Excerpt: Data from NASA’s now-retired Kepler Space Telescope reveals an eclectic assortment of new planets and planetary systems that promises to deepen understanding of how exoplanets form. Some of the newly-discovered planets might make tempting targets for the James Webb Space Telescope, now being fine-tuned for its first observations this summer. The Webb telescope is expected to search for signs of atmospheres around some exoplanets, and potentially determine some of the gases and molecules present. This raft of new planets also helped push NASA’s tally of confirmed exoplanets past the 5,000 mark in March 2022. ...Combing through Kepler data also revealed another potentially significant find: a possible exomoon. ...The new possible exomoon, Kepler-1708 b-i, would be very large for a moon, about 2.6 times as big around as E

Giant Planet’s Formation Caught in Action By Jure Japelj , Eos/AGU.  Excerpt: Astronomers took a direct image of a massive protoplanet embedded in a protoplanetary disk. The system provides strong evidence for an as-yet-unconfirmed theory of planet formation. ...Jupiter-class gas giants on far-flung orbits have challenged what is known as the standard formation scenario. Scientists  converged  on the scenario that our solar system’s giant planets formed via accretion within the gaseous protoplanetary disk. Rocky planetary cores fed on pebbles or planetesimals, and once the cores reached a certain mass, they began gobbling up the surrounding gas, rapidly becoming giant planets. But that process works only when planets form relatively close to their host stars—the gas giants found on wide orbits would not have had time to grow a sufficiently massive core before the gaseous disk dissipated. The unstable disk model is one of several alternative models  suggesting  

Imagine Another World. Now Imagine 5,000 More By Becky Ferreira , The New York Times.  Excerpt: NASA recently announced that it had detected more than 5,000 exoplanets, so we asked astronomers, actors and an astronaut to share their favorite worlds orbiting distant stars.…

What Sounds Captured by NASA's Perseverance Rover Reveal About Mars By NASA News.  Excerpt: A new study based on recordings made by the rover finds that the speed of sound is slower on the Red Planet than on Earth and that, mostly, a deep silence prevails. ​ Listen closely to sounds from Mars, recorded by NASA’s Perseverance: the rover’s mechanical whine and click in a light Martian wind; the whir of rotors on Ingenuity, the Mars helicopter; the crackling strike of a rock-zapping laser. An international team of scientists has done just that, performing the first analysis of acoustics on the Red Planet. Their new study reveals how fast sound travels through the extremely thin, mostly carbon dioxide atmosphere, how Mars might sound to human ears, and how scientists can use audio recordings to probe subtle air-pressure changes on another world – and to gauge the health of the rover. ...Most of the sounds in  the study , published April 1 in the journal Natu

Making a Camera That Works a Million Miles Away By Mark A. Stein , The New York Times interview.  Excerpt: When the James Webb Space Telescope sent its first images to Earth, no one was more excited than Marcia J. Rieke, who oversaw the design and construction of its camera. ...We’ve gotten the first images and we’re super happy. The entire Webb team is ecstatic at how well the first steps of taking images and aligning the telescope are proceeding. ... When did the astronomy bug bite you? As a kid, I read astronomy and science fiction books from the public library and became enchanted with the idea of visiting other planets. When I was in junior high, I worked as a babysitter and saved money to buy myself a telescope. ... This was in the late 1960s. How was it to be a woman in your field back then? My entering class was one of the first ones where M.I.T. made a big push to get more women accepted. In my class, there were something like 73 women