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Current time:0:00Total duration:1:32

Video transcript

want to make one clarification on my video of unsupervised a supernovae because that's the plural for supernovae is that I said this supernova occurred a thousand years ago that's actually not precisely right the supernova was first observed a thousand years ago or the light from that first explosion was observed by astronomers we believe a thousand years ago but we have to be very clear here because the Crab Nebula and at its core is roughly 6,500 light years away even this light even this image we see right here is that nebula as it was 6,500 years ago and so the supernova itself if we think about when it actually occurred it actually must have occurred about 7,500 years ago so it must have occurred about 7,500 years ago years ago and that first light from that first explosion from that first energetic event reached us about a thousand years ago so reach so it took 6,500 years to get to us and reached us a thousand years ago so first first light one thousand years ago one thousand years ago I just wanted to make that clear it might have been obvious to some of y'all but always important to think about it when I said a thousand years ago I really should have said it was first observed the explosion was observed a thousand years ago but since it's so far the actual event must have occurred 7,500 years ago