Today 21:00,The first black hole photo in history is about to be announced. This is a historic momen
Astronomers have always dreamed of "seeing black holes." Through unremitting efforts, this dream will be realized.
The Event Vision Telescope (EHT) is a telescope consisting of radio astronomy observatories around the world. Its resolution is equivalent to using a virtual telescope as large as the Earth. In April 2017, EHT aimed at a pair of gravitational monsters in the universe: one is the supermassive black hole Sagittarius A* in the center of the Milky Way, and the other is the supermassive black hole in the center of the M87 galaxy.
After a long period of data analysis, EHT finally announced a "breakthrough" result on April 10!
The first question everyone cares about is natural: what is a black hole? If everything is the same as general relativity, then the black hole image we see will be: a circular "contour" surrounded by a circle of bright photons:
A simulated image of a supermassive black hole in the center of the M87 galaxy. The black area in the middle is the outline of the black hole. Photo: Jason Dexter (left) and Kazunori Akiyama (right)
Simulation image of black hole contour: General relativity predicts that the contour is circular (middle), while other theories predict different shapes (left and right). Image: D. Psaltis and A. Broderick
On the eve of the EHT breakthrough results, astronomers first photographed the “dust ring” around the supermassive black hole in the Cygnus A center, which is an important part of the unified model of the active galaxy core (AGN). Image: Bill Saxton, NRAO / AUI / NSF
Some black holes are greedy animals that inhale a lot of gas and dust; others are picky devourers. No one knows the reason for this difference. Sagittarius A* seems to be the most critical category. Although it has a mass of 4 million solar masses, it has an incredible accretion disk. Another observation of the black hole EHT in the M87 galaxy is a greedy devourer. Surrounded by a bright accretion disk, it emits a bright, fast-charging jet of subatomic particles that extend to a distance of 5,000 light years.
EHT measurements of black holes in the center of the M87 galaxy will help estimate the strength of the magnetic field. Astronomers believe that the magnetic field strength of a black hole is related to the jet emission mechanism.
No matter what the final result of tomorrow is, it will be epoch-making, let us wait and see!