Einstein’s theory of general relativity predicted that black holes are the remnants of a massive star after it dies. His equations showed that if the leftover core of a massive star is more than approximately three times the mass of our sun, then the overwhelming force of gravity alone will produce a black hole.
About a year and a half ago, researchers at the University of California, Irvine picked up some interesting information: the Laser Interferometer Gravitational-Wave Observatory (or LIGO for short) detected ripples in the space-time continuum.
Here’s the crazy part: these ripples were found to have been caused by an ancient collision of two black holes (known as “binary black holes”) that occurred about 1.3 billion years ago. These black holes would’ve been about the size of 30 suns!
This whole thing is so significant because researchers had never seen a binary black hole merger before, let alone one that turned out to be so incredibly massive that it created ripples in the space-time continuum.
Because of these specific findings, the UCI researchers then conducted a “cosmic inventory” that determined that there are likely 100 millions black holes in the Milky Way alone, which is way more than what we originally thought!
LIGO researcher Eric Thrane of Monash University in Australia says, “The discovery of this gravitational wave suggests that merging black holes are heavier and more numerous than many researchers previously believed. This bodes well for detection of large populations of distant black holes … It will be intriguing to see what other sources of gravitational waves are out there, waiting to be discovered.”
Another reason this finding is so significant is that it confirms the last major prediction in Einstein’s general theory of relativity. It’s just one more piece of the puzzle that tells us how the universe is shaped by mass.
According to NASA, even if the sun were to one day randomly turn into a black hole of the same size, earth would not get sucked in. And lucky for us, black holes (just like everything else in the universe) follow the laws of gravity, meaning that they don’t go around randomly swallowing up planets. Phew!
UCI Astrophysicist James Bullock (pictured) says that “it’s not like we need to go out and buy black hole insurance soon; not like we’re in danger of being sucked into a black hole any more than we were before … It’s just amazing that the universe was created out of things like this.”