If you're seeing this message, it means we're having trouble loading external resources on our website.

If you're behind a web filter, please make sure that the domains *.kastatic.org and *.kasandbox.org are unblocked.

Main content
Current time:0:00Total duration:1:46

Video transcript

I want to make a quick correction to the video on quasars in that video I said and I mistakenly said that the quasars or that the chrétien disk that's really forming that or releasing the energy of the quasar that's releasing energy predominantly in the in the x-ray part of the electromagnetic spectrum and that was incorrect most quasars are actually emitting electromagnetic creation across the spectrum all the way from x-rays all the way from x-rays as high frequency as x-rays all the way down to infrared all the way down to para infrared and some quasars even release super high frequency gamma rays and they'll release low-frequency electromagnetic waves all the way down to radio waves so I just wanted to make that correction it's not predominantly in the x-ray part of the spectrum it's across the spectrum right over here it's this entire range of the spectrum and sometimes even a wider range now the other thing I want to clarify is this is the range of the spectrum that's being emitted but we have to remember that most or actually all of these collisions are quite far away the closest is 780 million light-years away many of them are many many billions of light-years away and so they're moving away from us at a very fast speed or because they're getting red shifted because the universe is expanding so fast relative to us at that point or that coordinate is moving so fast away from our coordinate and so even though this is the spectrum that's being emitted it's all going to be redshifted it's all going to be red shifted down and so we are going to observe things at a much at a much lower frequency maybe around the radio part of the frequency so everything will be red shifted down and that's why these were originally called quasi-stellar radio sources anyway hopefully that clears things up a little bit