Astronomy Picture of the Day

Explanation: The image above is part of the Hubble Deep Field and represents humanity's most distant yet optical view of the Universe. Galaxies like colourful pieces of candy fill the field, some as faint as 30th magnitude (about four billion times fainter than stars visible to the unaided eye). The dimmest objects are the most distant galaxies and reveal what the Universe looked like in the extremely distant past, perhaps less than one billion years after the Big Bang. To make the Deep Field image, astronomers selected an uncluttered area of the sky in the constellation Ursa Major (the Big Dipper) and pointed the Hubble Space Telescope at a single spot for 10 days accumulating and combining many separate exposures. With each additional exposure, fainter objects were revealed. The final result can be used to explore the mysteries of galaxy evolution and the infant Universe.