Astronomers have observed and recorded three titanic black holes on a collision course. This may sound like good news but the wait to finally see it happen; one billion years.
Several observatories, both in space and on Earth soil, were used to detect this unbelievable triple black hole system.
- According to various astronomers, this is the best evidence for the existence of actively feeding triple supermassive black hole systems. The system has been loosely named after the telescopes and observatories: SDSS J084905.51+111447.2 or SDSS J0849+1114 (supposedly “short”).
The Holy Trinity of these black holes coincidentally comes during the NASA’s Blackholes week.
Telescopes coming into observing the supermassive titans on the collision course:
- The first step of finding systems like these involves the Sloan Digital Sky Survey telescope (SDSS). SDSS scans massive parts of the sky, observing it in the visible spectrum of light. Sloan Digital Sky Survey Telescope found the trinity of black-holes on the collision course with the help of scientists participating in the project, Galaxy Zoo.
- This data was taken up by NASA’s Wide-field Infrared Survey Explorer (WISE) and the mission unveiled intense infrared light. Intense infrared light is consistent with galaxy merger phases when more than one black holes rapidly feed on nearby stars and stardust.
- Followup on the data was done using the NASA Chandra X-ray telescope and the Large Binocular Telescope in Arizona. Chandra X-Ray’s data showed X-ray sources which are also consistent with feeding black holes at the galactic centre. These Galaxy centres are the exact places where black holes are expected to exist.
Additional data from Chandra and NASA’s Nuclear Spectroscopic Telescope Array aka NuSTAR also showed large amounts of gas and space dust around one particular black hole, meaning it may be the biggest of them all.
Cloak of gas and space dust
- The first reason that makes it incredibly difficult to find and observe multi-black hole systems is the fact that they are more often than not cloaked under a shroud of gas and space dust. This is because of the fact that they are constantly consuming and more active in conjunction, fighting each other’s gravity with their own.
- Ultimately, the rarity of dual and triple black hole systems is only sensible. The evolution of the universe on a whole and formation of larger galaxies entails unimaginable amounts of time passing by as they grow closer to each other through the forces of gravity. Accounting for the expansion of our universe, this amount of time becomes even larger.
Triple black hole solving the Final Parsec Problem:
- When any two galaxies collide, the black holes at its centre do not collide head-on, instead, they pass by each other, escaping each other’s gravitational pull. Consequently, they lose energy as they pass by additional matter and stars, sending them in slingshot orbits around the black hole(s). Decelerated, the black holes lose kinetic energy (momentum/speed) and become bound to each other.
- Losing orbital energy, they move closer to each other until they are only a few hundred trillion kilometres from each other, a few Parsecs in celestial terms. This process also leads to ejection of matter from the orbital path. As the orbital distance reduces and the volume of space remaining is very little, the matter remaining in the dual black holes’ path is not enough to cause a merger between them in the age of our universe.
- The question of how the merger is possible in this calculative process is known as the Final Parsec Problem. Addition of a third galaxy coming into the mix adds additional matter for the black holes to consume, making the orbits more chaotic. This addition of matter gives blackholes the opportunity to consume more matter while also losing more orbital energy. This may lead to the eventual collision of blackholes as their gravitational waves come into effect within 0.1-0.001 Parsecs, leading to a triple black hole merger.
Introduction of a third black hole in the dual supermassive blackhole system is a possible solution to this theoretical problem. Now, all that we need is to wait for a billion years to oversee the collision finally occur.
