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As the "Improved Crystal" nickname implies, many believe that the KH-12 is largely an incremental improvement upon the KH-11, and a number of observers classify the spacecraft as a KH-11. Similarly, a successor KH-13 program may or may not currently exist (some have called that a "KH-12B").
The spacecraft's mirror is believed to be as large as or larger than that of the KH-11, believed to have a 2.3 meter diameter. It may be as large as 4 meters. As a point of comparison, the HST's mirror is 2.4 m in size. Jane's Defence Weekly indicates that the secondary mirror in the Cassegrain reflecting telescopeA reflecting telescope reflector is an optical telescope which uses mirrors, rather than lenses, to reflect light. The British scientist Sir Isaac Newton designed the first reflector circa 1670. He designed the reflector in order to solve the problem of c system can be moved significantly, allowing images to be taken from angles unusual for a satellite. Also, there are indications that the satellite can take images every 5 secondThis article is about the unit of time. See second (disambiguation) for other uses The second (symbol s is a unit for time, and one of seven SI base units. It is defined as the duration of 9,192,631,770 periods of the radiation corresponding to the transis. Sources vary on how the KH-12 communicates with ground stations. Several different clusters of relay satellites are available, so the birds may use the Satellite Data SystemThe Satellite Data System SDS is a system of United States military communications satellites. At least two generations have been used: SDS-1 from July 1976 to November 1995, and SDS-2 from 1989 to the present. SDS satellites have a highly elliptical orbi (SDS), MILSTAR , or Tracking and Data Relay Satellite System (TDRSS) networks.
At least 3 were launched between February 1990Events January January 3 Former leader of Panama Manuel Noriega surrenders to American forces. January 7 The Leaning Tower of Pisa is closed to the public due to safety concerns. January 9 Lt Gen Bazilio Olara Okello The man who led the coup aginst Dr Apo and December 19961996 was a leap year starting on Monday (see link for calendar), and was designated the International Year for the Eradication of Poverty''. Events January January 5 Hamas operative Yahya Ayyash is killed by an Israeli-planted booby-trapped cell phone Jan, and others have probably been launched since. It is believed that one was released by the Space Shuttle AtlantisThe Shuttle Orbiter Atlantis (Designation: Orbital Vehicle 104, or OV-104) is one of five NASA space shuttles. It was the fourth shuttle built and as of 2004 is one of the three shuttles remaining in the fleet. The Atlantis was named in honor of the first on STS-36Mission Insignia Mission Statistics Mission:STS-36 Shuttle: Atlantis Launch Pad:39-A Launch:February 28, 1990,2:50:22 a. EST Landing:March 4, 1990,10:08:44 a. PST Duration:4 days, 10 hours,18 minutes, 22 seconds Orbit Altitude:132 nautical miles Orbit Inc, though others were launched on Titan 4 rockets.
KH-12 satellites are believed to have been the source of some imagery of Russia and China made public in 1997, as well as images of Sudan and Afghanistan made public in 1998 that were related to the response to the 1998 U.S. embassy bombings.