Added 1 new A* page:Man there's been loads of interesting articles in the past few weeks, I need to do a SPACE NEWS ROUNDUP! (even a bunch of A* / supermassive black hole stuff in there):
Possible Ice Volcano on Pluto Has the ‘Wright Stuff’ (NASA) - one of two possible cryovolcanoes (volcanoes that spew ice instead of magma!) found on Pluto: the 90-mile-wide, 2.5 mile high Wright Mons
Advance in astronomy 'can help find other worlds' (BBC) - the usual method of determining a star's gravity by gauging its average brightness generally only works for close, bright stars, but a new method based on studying variations in the star's brightness may have a much wider application, allowing many more stars to be measured
Black hole caught 'burping' galactic gas supply (BBC) - two huge arcs of gas around the supermassive black hole at the center of galaxy NGC 5195 are found to have been expelled in the black hole's active phase; plus, a binary pair of supermassive black holes, possibly from the merger of a galaxy and a dwarf galaxy, because only one has stars orbiting it—the smaller may actually be a theorized but never yet conclusively detected intermediate-mass black hole
Diamond squeeze hints at metallic hydrogen (BBC) - scientists squish hydrogen molecules between two diamond tips so hard the hydrogen turns solid, then takes on a crystalline structure, possibly close to a long-predicted but never seen "metallic" state, in which the hydrogen can conduct electricity; metallic hydrogen is thought to make up a significant fraction of the intensely pressurized interior of Jupiter (and similar planets), and would explain help account for the planet's very powerful magnetic field
Star clumps harbour 'sweet spot' in search for alien life (BBC) - I try to avoid clickbait "alien life" articles, but this one does talk about the type of environment in a dense star cluster that might be conducive to interplanetary life—like in the dense star regions around the galactic center where A* is set: regions where the stars aren't so densely packed that planetary systems are broken up by gravity from other stars, but are still close enough together for travel from one to the other
Largest ever 'age map' traces galactic history (BBC) - using a formula they developed from known data to estimate the masses of stars in our galaxy based on their color spectra, scientists estimated the ages of 70,000 stars in our galaxy, creating a galactic "age map" illustrating what has already been theorized: the galaxy formed from the inside (now older stars) out (to the more distant, younger stars, like the Sun)
Event horizon snapshot due in 2017 (BBC) - by 2017, a network of radio telescopes hopes to capture a photo of the event horizon of the supermassive black hole at the center of our galaxy: Sagittarius A*! Not only is that super-exciting for us A* fans, it would be the first time any black hole has actually been seen directly. A*'s event horizon is "17 times bigger than the Sun," but it's also "25,000 light years away" (more like 25,900, according to Wikipedia) and shrouded in gas and dust, so getting a photo isn't easy. Actually seeing the black hole would allow scientists to begin to learn how physics behave in such space-warping conditions, and to test how Einstein's theory of general relativity really holds up. In an audio clip in the article, a science team member talks about what our models say an event horizon should actually look like: a crescent, because stuff whips around it so fast that the wavelength of the light from the side on which the stuff is rotating toward us is squished—Doppler shifted—and becomes much brighter than the light from the side that is spinning away, which gets correspondingly stretched and fainter. (Although she doesn't help her case for scientific reliability by not catching that at ~3:25 she mistakenly says A* is "26 million light years" away from us, rather than its actual 26 *thousand* light year distance. : p)
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