(Image source: NASA / Space.com)
BY STEVEN SPARKMAN
Just days after NASA announced the discovery of the largest black hole on record, they’ve pushed the boundary in the other direction -- the smallest black hole on record. And that little black hole barely became one at all.
“The black hole itself is only about three times the mass of the Sun, which means that the original star was just barely big enough to form a black hole. Our Sun, by contrast, lacks sufficient mass to form a black hole at the end of its life-cycle.”
So how did NASA find this baby-sized black hole? Just like a human baby is found -- by recording its heartbeat. Space.com explains.
“The researchers can't directly observe the black hole, but they measured a rise and fall in X-ray light coming from a binary star system in our Milky Way galaxy that they think signals the presence of a black hole. Until now, this X-ray pattern, which is similar to a heartbeat registered on an electrocardiogram, has been seen in only one other black hole system.”
The heartbeat is caused by gasses heating up as they near the event horizon -- or the black hole’s edge. The tiny black hole is near a star, which feeds it a constant stream of solar gas. When the gas gets hot enough, it pushes out away from the black hole, stopping the feed. Then, it cools down and begins falling into the hole again. The process can take as little as 40 seconds and makes the signal look like a heartbeat. (Video source: NASA)
But how does NASA know this is the smallest black hole? The last smallest black hole that was found also made this kind of pattern -- but, it took several hours to cycle instead of seconds. The Boise Weekly quotes a NASA scientist:
“Just as the heart rate of a mouse is faster than an elephant's, the heartbeat signals from these black holes scales according to their masses...”
The system is located in the direction of the constellation Scorpius, though researchers haven’t yet pinned down how far away it is.
