| | Hubble Deep Field Encyclopedia Article @ LaunchBase.com (Launch Base) (Site not responding. Last check: 2007-09-19) |
 | | The Hubble Deep Field (HDF) is an image of a small region in the constellation Ursa Major, based on the results of a series of observations by the Hubble Space Telescope. |
| | The HDF field is at the centre of this image, one degree across, which shows the unremarkable nature of this patch of sky. |
| | Because the quantum efficiency of Hubble's detectors is quite low at 300 nm, the noise in observations at this wavelength is primarily due to CCD noise rather than sky background; thus, these observations could be conducted at times when high background noise would have harmed the efficiency of observations in other passbands. |
| www.launchbase.com /encyclopedia/Hubble_Deep_Field (1794 words) |
