In news that reads like the beginning of a dire science fiction novel Sagittarius A*, the supermassive black hole at the centre of our galaxy, has emitted a large burst of infrared radiation brighter than anything ever produced by that black hole. The black hole is well-known to scientists, and was one of the subjects of our first ever efforts to image the cosmic beasts, but its still throwing up new mysteries all the time.
After observing for over four days using the Keck II Telescope in Hawaii, a team that has been studying Sagittarius A* for 20 plus years noticed the infrared light increased by 75 times.
Here's a timelapse of images over 2.5 hr from May from @keckobservatory of the supermassive black hole Sgr A*. The black hole is always variable, but this was the brightest we've seen in the infrared so far. It was probably even brighter before we started observing that night! pic.twitter.com/MwXioZ7twV
— Tuan Do (@quantumpenguin) August 11, 2019
Scientists aren't quite sure why this strange flash occurred, but it's apparently nothing to be concerned about.
Speaking to ScienceAlert, Tuan Do (an author on the study which spotted the bright light) said the flash could be the result of another star (S02) passing close by, thereby changing the way gas flows into the black hole. Another working theory is the flash was caused by G2, a gas cloud which also recently passed close (36 light-hours) to the black hole in 2014. There is a possibility this is a delayed reaction to that event.
Taken when I was @keckobservatory, this raw image shows the brightest Sgr A* has ever been observed in the infrared (center). The emission associated with the black hole also changed by a factor of 75 over that night. Is Sgr A* waking up? Will we finally see 🎆? pic.twitter.com/lX7ZO2PhX2
— Tuan Do (@quantumpenguin) August 8, 2019
Other teams and telescopes, such as Spitzer, Swift, Chandra, and ALMA, have also been observing Sagittarius A*. Do is curious to see if they too spotted the strange emission. Perhaps that data can help shed new light on this strange burst of infra-red light.
