6 STAMPS :
UHURU XIV: 12 Dec. 1970, Japan - experimental satellite for XRay.
ROSAT 16: 31 Mai 1990. German satellite - XRay Observatory, over 120.000 XRay sources detected. Start by US Delta rocket from KSC, ROSAT is the abbreviation of Roentgen Satellite.
IUE: 26 Jan. 1978. ESA Satellite for XRay Astronomy - IUE is name of International Ultra-violet Explorer - Cooperation ESA-NASA-England.
ASTRO E: 11 Fev. 2000. FUTURE Nippon project for XXI¡ century, advanced XRay observatory.
EXOSAT: 26 Mai 1983. ESA X-Ray Satellite - Put in orbit by American rocket DELTA from Vandenberg Air Force Base (CA).
CHANDRA: 23 Juillet 1999.(AXA F) Nasa Space Telescope as Hubble, but for XRay, named in memory to Indian scientist CHANDRA.
X.M.M: 10 Dec. 1999. 1st X ESA.
On the frame of sheetlet 2 :
XMM Launch Dec. 10 1999 First XRay telescope of ESA, launched by ARIANE 5 V119, first commercial launch of the new European rocket, weight XMM 3.900 Kg. XMM is the complementary of Chandra Nasa Satellite.background : XRay picture of black hole in the Crabe Nebulae