Hubble deep field-south unveils myriad galaxies
23 November 1998A Hubble Space Telescope "view down a 12 billion light-year long corridor of space loaded with a dazzling assortment of thousands of never-before seen galaxies", says the NASA press release.This picture is the culmination of a 10-day long observation called the Hubble Deep Field South (HDF-S) carried out in October by a team of astronomers at the Space Telescope Science Institute (STScI) and Goddard Space Flight Center.
This new "far-look" complements the original Hubble "deep field" taken in late 1995. The new regions studied is in the constellation Tucana, near the south celestial pole.
Hubble allows astronomers to sort galaxy shapes. The image is dominated by pinwheel-shaped galaxies, which are like our Milky Way.The picture also contains a variety of peculiar-shaped galaxies that are in collision with companion galaxies. Elliptical galaxies appear as reddish blobs. A sprinkling of foreground stars (belonging to our Milky Way) appear as bright points with "diffraction spikes" an artifact of all telescope optics.
The colours in the pictures are a natural representation of the galaxies' stellar populations. Blue corresponds to young hot stars. Red may indicate older stars, starlight scattered by dust, or very distant starlight that has been stretched to redder wavelengths by the universe's expansion.
Follow-up observations with large ground-based telescopes in the southern hemisphere will establish the distances to the galaxies. This will help astronomers understand the history of the universe because the galaxies represent the universe at different epochs, depending on their distances.
On 23 November 1998 at 3:00 pm EST the entire HDF-S dataset, consisting of both raw and pipeline-processed data, was made publicly available from the HST Archive.