Swirling rings of light orbiting, and being sucked into, a black hole, could act as a movie of the Universe, researchers have discovered. These ‘rings’ are akin to tree rings, which help to determine the age of a tree, according to research from a team of US physicists.
The team analysed the photons – light particles – swirling around the black hole at the centre of the galaxy M87, some 55 million light years away from Earth.
Scientists discovered that these photons can act as if they are “frames” of a movie, giving insight into how the black hole formed and the activity around a black hole.
The research paper said: “The Event Horizon Telescope image of the supermassive black hole in the galaxy M87 is dominated by a bright, unresolved ring.
“General relativity predicts that embedded within this image lies a thin ‘photon ring,’ which is composed of an infinite sequence of self-similar subrings that are indexed by the number of photon orbits around the black hole.
“The subrings approach the edge of the black hole ‘shadow,’ becoming exponentially narrower but weaker with increasing orbit number, with seemingly negligible contributions from high order subrings.”
It continued: “Together, the set of subrings are akin to the frames of a movie, capturing the history of the visible universe as seen from the black hole.”
However, each ring is only six days older than the last and quickly get gobbled up by the immense gravitational pull of the black hole known as Pōwehi, massively limiting how far back the researchers can see.
Harvard astronomer Michael Johnson, who worked on the research, told New Scientist: “We’re not going to see dinosaurs.”
Scientists believe the most common instance is when a star, thousands of times the size of our sun, collapses in on itself when it dies – known as a supernova.
Another way is when a large amount of matter, which can be in the form of a gas cloud or a star collapses in on itself through its own gravitational pull.
Finally, the collision of two neutron stars can cause a black hole.