http://www.rssboard.org/rss-specification 720 http://ecuip-xtf.lib.uchicago.edu/xtf/search?expand%3Dsubject;f1-spectral-Type%3DX-ray;f2-associated-Lesson%3DX-Ray%20History Results for your query: expand=subject;f1-spectral-Type=X-ray;f2-associated-Lesson=X-Ray History Thu, 01 Jan 1970 12:00:00 GMT http://ecuip-xtf.lib.uchicago.edu/xtf/view?docId=grxr/cygx1_xray/cygx1_xray.dc.xml Since its discovery in 1962, the X-ray binary star Cygnus X-1 has been one of the most intensively studied cosmic X-ray sources. About a decade after its discovery, Cygnus X-1 secured a place in the history of astronomy when a combination of space-based, X-ray observations by the Chandra X-ray Observatory and optical, ground-based observations by the Digitized Sky Survey led to the conclusion that it was a black hole, the first such identification. This is a Chandra X-ray image of Cygnus X-1. http://ecuip-xtf.lib.uchicago.edu/xtf/view?docId=grxr/cygx1_xray/cygx1_xray.dc.xml Thu, 01 Jan 1970 12:00:00 GMT http://ecuip-xtf.lib.uchicago.edu/xtf/view?docId=grxr/heao1-sky-map/heao1-sky-map.dc.xml Beginning in 1977, NASA launched a series of very large scientific payloads called High Energy Astronomy Observatories (HEAO). The first of these missions, HEAO-1, carried NRL’s Large Area Sky Survey Experiment (LASS), consisting of 7 detectors. It surveyed the X-ray sky almost three times over the 0.2 keV - 10 MeV energy band and provided nearly constant monitoring of X-ray sources near the ecliptic poles. http://ecuip-xtf.lib.uchicago.edu/xtf/view?docId=grxr/heao1-sky-map/heao1-sky-map.dc.xml Thu, 01 Jan 1970 12:00:00 GMT http://ecuip-xtf.lib.uchicago.edu/xtf/view?docId=grxr/misc_gx5-1_moon/misc_gx5-1_moon.dc.xml This image of the Moon in X-rays was made in 1991 using data from the Roentgen Satellite (ROSAT), an X-ray observatory. In this picture, pixel brightness corresponds to X-ray intensity. The Moon reflects lower energy X-rays (shown as red) from the Sun. The source of high energy X-rays (shown as yellow) is a distant binary star system. The background is speckled with X-rays from many distant, powerful active galaxies. The picture also shows the Moon passing in front of of and obscuring the binary star, a phenomenon called occultation. http://ecuip-xtf.lib.uchicago.edu/xtf/view?docId=grxr/misc_gx5-1_moon/misc_gx5-1_moon.dc.xml Tue, 01 Jan 1991 12:00:00 GMT