http://www.rssboard.org/rss-specification 720 http://ecuip-xtf.lib.uchicago.edu/xtf/search?f4-type%3DObservation;f5-associated-Lesson%3DX-Ray%20History Results for your query: f4-type=Observation;f5-associated-Lesson=X-Ray History Thu, 01 Jan 1970 12:00:00 GMT http://ecuip-xtf.lib.uchicago.edu/xtf/view?docId=grxr/cygx1_optical/cygx1_optical.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 an optical image of Cygnus X-1. http://ecuip-xtf.lib.uchicago.edu/xtf/view?docId=grxr/cygx1_optical/cygx1_optical.dc.xml 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/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