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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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Поисковые слова: propulsion
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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