EIS / 8X

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.

The FIA optical satellites were designed as their successors, but also failed. The relation to the stealthy Misty satellites is unclear, but Misty might have common elements with the 8X/EIS design.

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.