A cloud of matter with about the mass of 50 Earths will fall into the black hole at the center of the galaxy in a little over a decade, according to astronomers at a Maunakea observatory.
Since 2002, astronomers at Keck Observatory have tracked the behavior of X7, a vast cloud of dust and gas traveling on a centuries-long orbit around Sagittarius A*, the supermassive black hole at the center of the Milky Way.
A study published Tuesday in “The Astrophysical Journal” concluded that the cloud’s journey likely will end in 2036, when its trajectory approaches the black hole most closely.
“It’s not necessarily getting sucked in,” said Randy Cambell, co-author of the study and science operations lead at Keck. “But 2036 is when it will get closest to the black hole, and it will most likely break apart at that point.”
Because of the extreme gravitational forces acting upon X7, the cloud has become “spaghettified”: an actual scientific term describing how the tidal forces of a black hole tend to vertically stretch and horizontally compress matter into noodle-like shapes.
The X7 noodle is about 3,000 times as long as the distance between the Earth and the sun and traveling at about 490 miles per second.
Campbell said the long-running observation of X7 is not because the cloud is particularly notable in and of itself, but because its orbit allows astronomers to learn more about the black hole and the evolution of the galaxy.
“The Milky Way black hole is not like other supermassive black holes we’ve observed,” Campbell said. “Ours is quieter, it’s not sucking in as much material as others. Other black holes are gobbling up material all the time.”
Campbell said that watching X7’s final years will help researchers learn more about the black hole’s accretion process — the process by which surrounding matter is pulled into a close orbit around a gravity well, which often forms a disk-shaped collection of material.
That accretion process, Campbell said, could be what formed the Milky Way in the first place. While it is still uncertain whether galaxies form around supermassive black holes or if supermassive black holes form in the hearts of galaxies, he said that astronomers generally presume that all galaxies have black holes at their cores.
“It’s a privilege to be able to study the extreme environment at the center of our galaxy,” Campbell said. “This study can only be done using Keck’s superb capabilities and performed at the revered Maunakea, with honor and respect for this special site.”
Email Mike Brestovansky at mbrestovansky@hawaiitribune-herald.com.
