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Few things can take us further into the past than the Hubble Space Telescope. Orbiting nearly 600 kilometers above us frees it from the distorting effects of the Earth's atmosphere. We can see things that are approximately 10 billion times fainter than you can see with the unaided eye. We can easily see the light from a firefly at the distance of the Moon. Hubble's ability to see into deep space has produced one of the most revealing glimpses of the early universe we have. Yet it started as a shot in the dark. We formulated a plan by which we would point the telescope at an otherwise ordinary and blank spot in the sky...and expose long enough that we would just be able to reveal whatever was there. I've got on this screen here a picture of the sky. We were interested in a part of the sky called Fornax. This tiny piece of sky, the size of a pinhead held at arm's length. As the telescope started to send back images, Beckwith couldn't be sure they would reveal anything new. I've zoomed in on the first image right here, and you see, these are galaxies, okay? These are clearly galaxies, but the rest of it is just noise. Only by amassing a total of 400 individual images could this dark corner of the universe be illuminated. Okay, so now, what I'm going to do is Ifll build up the image. You'll begin to see faint things here, you see these things? And indeed, you can see them coming out. You can see all of this, see how beautiful that is? So as you add more and more images together, pretty soon now these things look quite bright. In the end, we exposed the telescope to the sky for a million seconds. It's the longest exposure that's ever been taken with an optical telescope. All of a sudden, all these faint things just emerge clean from the noise, and that's the process. That's how it works. If I had another million seconds, itfll look even better.