Lyman alpha emissions at 121.6 nm in the extreme ultraviolet from the hydrogen coma of a comets C/2012S1 , 2P/Encke and C/2013 R1 Lovejoy

Lyman alpha emissions at 121.6 nm in the extreme ultraviolet from the hydrogen coma of a comet must be monitored from outside earth's atmosphere. Spacecraft such as SOHO SWAN instrument and SWIFT UVOTS can see in Lyman alpha. Also the process of charge exchange generates X-Rays. Lyman alpha and X ray emission in comets has been observed in comets with SWIFT XRT, XMM-Newton, CHANDRA ACIS, ROSAT Deep Survey Camera HRI, Extreme Ultraviolet Explorer satellite (EUVE), Odin satellite, OGO-5 satellite, GALEX Near Ultraviolet (NUV), and Orbiting Astronomical Observatory (OAO-2). Stunning image SWAN / SOHO of the day October 29, 2013, which has captured the Lyman-Alpha emission in 121.6 nm of the 3 most visible comets now in the far UV, the image gives us scientific information about Crown H forming these comets coma due to the process known as fluorescence ionized atoms and molecules of H, N, C and O, namely the dissociation of H2O in OH and H, when sunlight falls on this, and in a roundabout way gives us information about the broadcast of the core sublimated water and decomposed by the solar wind, as you can see in my image processed, as much emission in the corona of H is in comet C/2013 LOVEJOY R1, followed by the 2 P / ENCKE, and finally the comet C/2012 S1 ISON which can be called the'' failed'' comet of the year unless post-perihelion surprises ... More information in Cometary Investigation Astrophysic Group FB ( CIAG_FB )