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English: Illustrates cumulative absorption spectra observed by Hubble.
A beam of light coming to Earth from a distant quasar passes through numerous intervening gas clouds in galaxies and in intergalactic space. These clouds of primeval hydrogen subtract specific colors from the beam. The resulting "absorption spectrum," recorded by Hubbles Space Telescope Imaging Spectrograph (STIS) is used to determine the distances and chemical composition of the invisible clouds.
Date 23 November 1998
( Reusing this file)


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