They say it all has to do with a galaxy cluster and a cosmic lens
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00:00When looking deep into space, we're actually peering back in time at light that was produced
00:08possibly millions of years ago.
00:10But back in 1979, astronomers noticed a pair of supermassive black holes at the center
00:15of two gas-filled galaxies, also known as quasars.
00:18But it turned out those two quasars were actually the same object, with one of the images delayed
00:23by something out in space.
00:24Recently, a team of astronomers from the University of Valencia discovered the same thing happening
00:29again.
00:30Over the course of 14 years, they clocked a 6.73 year delay between the two images of
00:34the same quasar.
00:36Experts say that the nearby cluster of galaxies is the culprit, creating a sort of cosmic
00:40gravitational lens that distorts the light that passes through it.
00:44That lens changed the light's path, forcing it to seemingly slow down and producing multiple
00:48images of the same object in space at different points in time.
00:51In the case of this newer quasar, four images, with the researchers writing, since the trajectory
00:56followed by the light rays to form each image is different, we observe them at different
01:00instants of time.
01:01In this case, we have to wait 6.73 years for the signal we observed in the first image
01:06to be reproduced in the fourth one.