Astronomers Closer to Cracking Mystery of Black Hole Formation

Black hole and star

Black hole cannibalizing sister star in binary system.

Scientists are closer like never before to understanding how black holes formed. They managed to build computer models based on ancient gravitational waves, i.e. the footprint of collisions between two black holes, and the findings were astounding.

According to the models, black holes are the remains of ancient supermassive stars locked in binary systems. These stars weighed up to 96 times the mass our parent star. After their death, the stars morphed into massive black holes that remained paired to one another until they merged into one black hole.

In the wake of the cosmic collision, monster shockwaves swept the Universe having an influence even on the time-space fabric. One such monster shockwave was detected from our planet on Sept. 14, 2015.

Researchers explained that such gravitational waves are the only evidence of the existence of ancient pairs of black holes, just like the fossils tells us that dinosaurs had once roamed the Earth.

Ancient black hole mergers are currently the largest known source of gravitational waves, researchers said. Other sources are collisions between massive neutron stars, or between these stars and black holes. The best fit instrument to capture these waves is Laser Interferometer Gravitational-wave Observatory (LIGO).

Scientists operating LIGO said that the instrument should be able to record about 1,000 mergers per year. But that will be possible by year 2020 when the observatory is expected to reach 100% sensitivity. When that happens a new era for ancient black hole research will begin.

Astronomers interested in gravitational waves suggested that their research will soon be very similar to that of paleontologists. In other words, astronomers will guess many details of stars from their remnants, just like paleontologists estimate how a dinosaur might have looked like from its fossilized remnants.

Researchers explained that the pair of stars detected on Sept. 14 contradicted their previous theories on where those stars should be located.

From the gravitational waves, scientists deducted that one star was more massive but exhausted itself quicker. Plus, the older star was soon cannibalized by its smaller partner who consumed its outer layer of gases through gravitational forces. After some time, the smaller star became the largest in the binary system.

In the meantime, the cannibalized star morphed into a black hole 35 times heavier than the Sun. In return, the black hole started ripping off its sister star’s gaseous layer enveloping it in a thick cloud of gas. Additionally, the black hole’s gravitational pull brought to star even closer, which also morphed into a black hole.

The two black holes orbited each other in total darkness and silence before colliding and briefly releasing more energy than all known stars in the universe combined, the models suggest.
Image Source: YouTube