Astro-2 and the UIT Experiment

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Дата изменения: Mon Oct 7 06:14:34 1996
Дата индексирования: Mon Oct 1 19:49:25 2012
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General Mission Science

By going above the earth's atmosphere instruments now have access to the ultraviolet portion of the electromagnetic spectrum . Ultraviolet photons have short wavelength and high energy and thus come from sources which have fairly high temperatures. Some of these sources include:

Stars hotter than 20,000 degrees (e.g. O and B stars)
Central stars of planetary Nebulae
Star formation regions in nearby galaxies
Star formation regions in our own galaxy
Normal Galactic Nuclei
Active Galactic Nuclei
Quasars and the search for Intergalactic Helium

In addition, the background glow of the night sky is at a minimum level at around 2000 angstroms. There exists a population of galaxies which have very low contrast with respect to the background. It is hoped that these very diffuse galaxies can be more easily imaged at a wavelength where the noise from a background of finite brightness is at its minimum.

The Electronic Universe Project nuts@moo.uoregon.edu