The EIS (Enhanced Imaging System) series of reconnaissance satellites, formerly known as 8X, were a planned replacement of the KH-11 Kennen/Crystal series.
The satellites were reportedly based on the KH-11 system and are believed to use a 2.4 m diameter prime mirror, but with a much larger field of view. Prime contractor for the EIS satellites was Lockheed Martin). The EIS, like the KH-11 series, were to transmit their data via relay satellites called Satellite Data System (SDS-2, SDS-3), which operate in Molniya orbits and geostationary orbits.
In August 2012, the NRO donated two telescopes with 2.4 m diameter prime mirror to NASA, which were left over from a defunct reconnaissance satellite program. These optics could possibly be remnants from the 8X/EIS program.
Possibly the EIS satellites are identical with the Block 4 version of KH-11.
|Type / Application:||Reconnaissance, electro-optical|
|Power:||Deployable solar arrays, batteries|
|EIS 1||-||cancelled||Va SLC-4E||Titan-4(04)B|
|EIS 2||-||cancelled||Va SLC-4E||Titan-4(04)B|