Astronomers working with the Hubble Space Telescope have just released the most detailed view of the early Universe ever captured. It's called the eXtreme Deep Field, or XDF for short. The image combines over ten years' worth of photographs by Hubble. It required 2-million seconds of exposure time to produce, and contains over 5,500 of the Universe's most ancient galaxies.
This image is more than jaw-dropping; to quote Hubble astronomers, this remarkable view pushes outward against the very frontiers of time and space.
Almost every visible object in this image is a galaxy, each one brimming with billions of celestial bodies. The most far-flung among them loom over 13-billion light years from Earth. The light that Hubble's instruments receive from these galaxies began its journey just a few hundred million years after the birth of the Universe.
From Earth, this light is almost unfathomably dim. On a moonless night, step outside and peer skyward. Let your eyes to adapt to the dark, and search the sky for the faintest star you can find. The light from that star is more than ten billion times brighter than the light arriving from this image's most muted objects. That Hubble can detect this light is nothing short of extraordinary. [Click here to see XDF in hi-res]
Equally impressive is the fact that this view captures but a tiny portion of the night sky. A full Moon spans an area of sky just one-half the width of a finger held at arm's length. XDF encompasses a fraction of that area:
NASA calls XDF a "time tunnel into the distant past." In a press release, Hubble Ultra Deep Field Principle Investigator Garth Illingworth said that "XDF allows us to explore further back in time than ever before."
As impressive as this image is, we can't help but be excited by those images still to come, specifically those acquired by the James Webb Space Telescope, set to launch in 2018. To quote astrophysicist Michael Shara, curator in the Department of Astrophysics at the American Museum of Natural History, whom we interviewed about JWST last year:
[The James Webb Space Telescope] has, in many ways, 100 times the capabilities that the Hubble Space Telescope does. We're actually going to be able to see the first stars forming, the first galaxies forming after the Big Bang. We're also going to be able to - we think - directly image planets orbiting other stars.
Read more about the Hubble eXtreme Deep Field, including a number of fantastic videos, over on HUBBLESITE. Hubble will also be hosting a public discussion about XDF on Google+ tomorrow, September 27th, beginning at 13:00 Eastern (US). You can tune in here.