Astro Blog

By Daniel Clery , Science.  Excerpt: Astronomers studying the murky center of our Milky Way Galaxy have discovered something they never expected:  a pair of young stars orbiting each other near the supermassive black hole that is our Galaxy’s dark heart . The observation—reported today in Nature Communications—comes as a surprise because astrophysicists had thought the black hole’s intense gravity would either rip the stars in such a pair apart or squash them together. But the new object, dubbed D9, shows that such a “binary” can survive, at least briefly, near the black hole, and it could help explain other mysterious objects in the vicinity. ...For many years, two teams, in California and Germany, monitored the  closest of those stars . About 20 years ago, both proved the star’s eccentric, high-speed orbit could only arise if it was circling a compact object with extreme mass—a black hole. For that work, the teams’ leaders, Reinhard Genzel of the Max Planck Institu...

By Daniel Clery , Science.  Excerpt: For years, astronomers thought it was the Milky Way’s destiny to collide with its near neighbor the Andromeda galaxy a few billion years from now. But a new simulation finds a 50% chance the impending crunch will end up a near-miss, at least for the next 10 billion years. ...It’s been known that Andromeda is heading toward our home Galaxy since 1912, when astronomer Vesto Slipher noted that its light is blue-shifted.... ...It wasn’t until the era of orbiting observatories that astronomers could judge Andromeda’s overall velocity in 3D.... It was, they calculated, heading pretty much straight at the Milky Way at a speed of 110 kilometers per second. ...A  study from 2008  suggested a Milky Way–Andromeda merger was inevitable within the next 5 billion years...ending up in...the resulting elliptical, which the researchers dub “Milkomeda.” The Milky Way, seen today as a bright band across the sky, would be replaced by a “milky blob” markin...

https://www.science.org/content/article/black-hole-center-milky-way-may-be-blasting-out-jet   By DANIEL CLERY , Science.  Excerpt: The supermassive black holes at the centers of many galaxies generate powerful jets, blasting particles thousands of light-years into space. This new image of the Milky Way’s black hole, known as Sagittarius A* (Sgr A*), suggests it may have one, too, but perhaps of a more modest nature. The image—taken with polarized light—was  released today by the Event Horizon Telescope (EHT) , a worldwide array of radio telescopes that in 2019 produced the  first ever image of a black hole . The new image shows light that is oriented in a particular direction, revealing magnetic field lines around the black hole. Although jets would not be visible in such a zoomed-in image, strong magnetic fields are thought to be essential in launching them.... See also European Southern Observatory press release . 

https://www.washingtonpost.com/science/2022/05/11/black-hole-milky-way 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 scal...

https://www.sciencedaily.com/releases/2020/08/200812115304.htm Source:   By Science Daily. Excerpt: Astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA), in which the European Southern Observatory (ESO) is a partner, have revealed an extremely distant and therefore very young galaxy that looks surprisingly like our Milky Way. The galaxy is so far away its light has taken more than 12 billion years to reach us: we see it as it was when the Universe was just 1.4 billion years old. It is also surprisingly unchaotic, contradicting theories that all galaxies in the early Universe were turbulent and unstable. This unexpected discovery challenges our understanding of how galaxies form, giving new insights into the past of our Universe. "This result represents a breakthrough in the field of galaxy formation, showing that the structures that we observe in nearby spiral galaxies and in our Milky Way were already in place 12 billion years ago," says Francesca Rizz...

https://www.sciencemag.org/news/2018/10/ball-gas-racing-around-black-hole-our-galaxy-s-heart Source:   By Daniel Clery, Science Magazine. Excerpt: Earlier this year, astronomers were looking for signs that S2, the star with the closest known orbit to the supermassive black hole thought to be at the center of the Milky Way, might—as predicted by Albert Einstein—deviate from the orbital path proscribed by Newtonian gravity. But while they were watching, they spied something else: three bright infrared flares unrelated to the star ...the signs of superheated gas racing almost as close to the black hole as possible without getting sucked in—at 30% the speed of light. Observing the action so close to the galactic center, known as Sagittarius A*, is extremely challenging because it is distant, small, and shrouded in gas and dust. The team used the world’s largest optical instrument, the European Southern Observatory’s Very Large Telescope in Chile, and combined the light of its four ...

https://www.nytimes.com/2018/05/01/science/gaia-map-milky-way.html Source:   By Dennis Overbye, The New York Times. Excerpt: ...astronomers in Europe released a three-dimensional map of the Milky Way. It is the most detailed survey ever produced of our home galaxy. It contains the vital statistics of some 1.3 billion stars — about one percent of the entire cosmic panoply of which Earth and the sun are part. Not to mention measurements of almost half a million quasars, asteroids and other flecks in the night. Analyzing all these motions and distances, astronomers say, could provide clues to the nature of dark matter. The gravity of that mysterious substance is said to pervade space and sculpt the arrangements of visible matter. Gaia’s data could also reveal information about the history of other forces and influences on our neighborhood in the void. And it could lead to a more precise measurement of a historically troublesome parameter called the Hubble constant, which describes...

Source:   Nick Risinger Excerpt: Nick Risinger … amateur astronomer and photographer quit his day job as a Seattle marketing director and lugged six synchronised cameras about 60,000 miles to capture an image of the entire night sky. He… stitched 37,440 exposures together into a spectacular, panoramic survey sky that he posted online ... a 360-degree view of the Milky Way, planets and stars in their true natural colors. Viewers can zoom in on portions of the 5,000-megapixel image to find Orion or the Large Magellanic Cloud.  Story:  www.dailymail.co.uk/sciencetech/article-1386348/Photographer-travels-60k-miles-year-compile-stunning-panorama-Milky-Way.html media.skysurvey.org/interactive360/index.html