Deuterium Abundance in the Local Ism Andpossible Spatial
نویسنده
چکیده
Excellent HST/GHRS spectra of interstellar hydrogen and deuterium Lyman-absorption toward nearby stars allow us to identify systematic errors that have plagued earlier work and to measure accurate values of the D/H ratio in local interstellar gas. Analysis of 12 sightlines through the Local Interstellar Cloud leads to a mean value of D/H = (1:50 0:10) 10 ?5 with all data points lying within 1 of the mean. Whether or not the D/H ratio has diierent values elsewhere in the Galaxy and beyond is a very important open question that will be one of the major objectives of the Far Ultraviolet Spectroscopic Explorer (FUSE) mission.
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