If you blinked, you missed them. Fortunately, astronomers at the University of Southampton were watching when the black hole V404 Cygni suddenly got active and they were rewarded with the sight of brief but incredibly intense red flashes coming out of rather than going into it. Is red the color you should wear if you want to avoid being sucked into a black hole?
Located 7,800 light-years from Earth in the Milky Way galaxy, black hole V404 Cygni got its first fifteen minutes of flame in June 2015 when astronomers noticed light coming out of it during a feeding frenzy (that’s what they called it) on a nearby star. The flare-up lasted about two weeks, giving astronomers an unprecedented amount of time to record the phenomenon.
Since the individual flashes are intense, with the brightness of 1,000 Suns, but brief, sometimes less than 1/40 of a second, astronomers used the ULTRACAM fast imaging camera mounted on the William Herschel Telescope in La Palma on the Canary Islands. According to the new report in the journal Monthly Notices of the Royal Astronomical Society, that’s how the were able to spot the red flashes. Dr. Poshak Gandhi, Associate Professor and STFC Ernest Rutherford Fellow in the University of Southampton’s Astronomy Group, gives their conclusions:
The very high speed tells us that the region where this red light is being emitted must be very compact. Piecing together clues about the colour, speed, and the power of these flashes, we conclude that this light is being emitted from the base of the black hole jet. The origin of these jets is still unknown, although strong magnetic fields are suspected to play a role.
If you’re planning to visit a black hole, you may not want to go when it’s eating. Dr. Gandhi describes what might happen as only an astronomer in love with observing black holes can:
Furthermore, these red flashes were found to be strongest at the peak of the black hole's feeding frenzy. We speculate that when the black hole was being rapidly force-fed by its companion orbiting star, it reacted violently by spewing out some of the material as a fast-moving jet. The duration of these flashing episodes could be related to the switching on and off of the jet, seen for the first time in detail.
This new information about black holes is the result of astronomers around the world at many observatories and labs sharing their data and notifying each other quickly when they notice something unusual.
Sounds like a good philosophy for all of us.