http://www.rssboard.org/rss-specification 720 http://ecuip-xtf.lib.uchicago.edu/xtf/search?f55-facility%3DCopernicus%20(OAO-3) Results for your query: f55-facility=Copernicus (OAO-3) Thu, 01 Jan 1970 12:00:00 GMT http://ecuip-xtf.lib.uchicago.edu/xtf/view?docId=grxr/1975ApJ___197___85M/1975ApJ___197___85M.dc.xml The spectrum was recorded with the Copernicus satellite (1972) by Don Morton. The abscissa (x-axis) is in units of Ångstroms and the ordinate (y-axis) is in units of counts per 14 seconds. The spectrum was recorded point by point using a photo cell. The spectrum from 1197 Å to 1254 Å, which took 20 hours to record, contains four types of features: a) the strong absorption from the interstellar hydrogen line known as Lyman alpha near 1216 Å; b) a set of very narrow, deep lines due to neutral nitrogen at 1200 Å, twice ionized silicon at 1206 Å, and once ionized sulfur just past 1250 Å, all from interstellar gas; c) a wind containing four times ionized nitrogen blowing off the surface of the star at 1000 km/second (1233 Å and 1238 Å); d) general undulations across the top which are due to absorption lines in the atmosphere of the star itself. The sharp, narrow interstellar lines, item b, actually contain two components which cannot be distinguished in this spectrum because of insufficient resolution. This is the... http://ecuip-xtf.lib.uchicago.edu/xtf/view?docId=grxr/1975ApJ___197___85M/1975ApJ___197___85M.dc.xml Sat, 01 Jan 1972 12:00:00 GMT