Astrophysicists have discovered a dozen black holes —“invisible one-way doors out of our universe” —gathered around Sagittarius A* (Sgr A*), the supermassive black hole in the center of the Milky Way Galaxy, which in May, 2019 suddenly brightened, appearing like a massive, dormant volcano.
“If this monster was at the center of the Milky Way it would likely make life on Earth impossible with the huge amounts of x-rays emanating from it,” said Christian Wolf, with the Australian National University (ANU) Research School of Astronomy and Astrophysics who made the momentous detection in 2018. “It would appear 10 times brighter than a full moon, an incredibly bright pin-point star that would almost wash out all of the stars in the sky. It’s probably 10,000 times brighter than the galaxy it lives in.” So bright, that it if we were approaching the galaxy in a starship, the object would so blind our view that we could not see the galaxy itself.
“Somewhere,” said Carl Sagan, “something incredible is waiting to be known” –“I’ve never seen anything like this before in the local universe,” said Stephen Smartt, an astrophysicist at Queen’s University Belfast and a lead scientist for the Hawaii-based ATLAS survey, about “something incredible” –a mysterious cataclysm in a neighboring galaxy that rocked the world’s astronomy community with its discovery on June 16, 2018.
Hubble’s infrared eye unveiled an enormous flash from Milky Way’s black hole about 3.5 million years ago that lit up a portion of a massive ribbon-like gas structure called the Magellanic Stream of high-velocity clouds of gas torn out of the Magellanic Clouds hundreds of millions of years ago, extending from the Large and Small Magellanic Clouds through the Galactic south pole of the Milky Way. The flash ionized its hydrogen (enough to make 100 million Suns) by stripping atoms of their electrons. The radiation cone was surely witnessed by Earth’s early hominids, already afoot on the African savannas as the ghostly glow spread high overhead in the then unnamed constellation Sagittarius.
In January of 2019, astronomers at the W. M. Keck Observatory on Maunakea, Hawaii and the University of Hawaii Institute for Astronomy’s ATLAS twin telescopes, reported evidence of the exact moment a star collapsed to form a compact object, such as a black hole or neutron star. They dubbed the object “The Cow”, shown in the image above, just visible as one of two bright spots in the lower right quadrant of the spiral galaxy classified as CGCG 137-068. The objects incredibly bright glow –10 to 100 times brighter than a typical supernova–was caused by stellar debris, swirling around its event horizon.
In 2010, astronomers working with the Fermi Gamma-Ray Space Telescope revealed a previously unseen structure centered in the Milky Way that spans 50,000 light-years that was hypothesized to be the remnant of an eruption from Sgr A*, the supermassive black hole at the center of our galaxy. The bubble emissions, much more energetic than the gamma-ray fog seen elsewhere in the Milky Way, spans more than half of the visible sky, a region roughly as large as the galaxy itself, and it may be millions of years old, its origin, until now, an unsolved mystery.
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