In 1995, the Space Telescope Science Institute (operators of the Hubble Space Telescope) released the Hubble Deep Field, a groundbreaking piece of astronomy comprised of 342 exposures taken over a ten day period of just one tiny and nearly featureless part of Ursa Major. It was a revelation, because when the data came back, the space was not featureless but dotted with a myriad of distant galaxies.
A tremendous amount of science has been done with the Hubble Deep Field; among other things, it reinforced the notion that the Universe is broadly uniform even at great distances. But the Hubble wasn’t done. The feat was repeated a few years later in the southern sky, producing the Hubble Deep Field South and the Great Observatories Origins Deep Survey, which combined deep field images from Hubble, Chandra, Spitzer, XMM Newton, and even ground-based observatories. (GOODS has since been amplified further with data from Herschel.) In 2003, Hubble did it again, producing the Hubble Ultra Deep Field, enhanced in a stunning image in the constellation Fornax revealing galaxies almost as far away (and as far back in time) as it is possible to see. In 2009, infrared data was added, courtesy of the Wide Field Camera 3, installed on the final Hubble servicing mission that year, and in 2012, a zoomed-in version was created, called the Hubble Extreme Deep Field, revealing galaxies 13.2 billion light years away.
Well, the HUDF has been updated again, now with the full spectrum from ultraviolet to infra-red. And it is gorgeous. Click it to go to the HubbleSite page with full resolution versions. You won’t regret it.