NASA will be performing network maintenance on Thursday, May 13 from 3:00pm - 8:00pm (1900 UTC - 0000 UTC). You may experience network difficulties accessing ALL CDDIS services. You may experience outages as long as 15 minutes and multiple short (several minute) intermittent outages as well during the maintenance window.

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Lunar laser ranging data

A subset of the global network is capable of laser ranging to retroreflectors placed on the lunar surface by NASA Apollo and Russia Lunakod missions in the 1969–1973 time period. The CDDIS archive of these data, in LLR-specific formats in early years and ILRS format since 1998, dates back to 1969. In a sense, the Moon and its retroreflectors can be considered another "satellite"; however, not all systems in the ILRS network have lasers powerful enough to reach lunar distances. Today, a subset of the ILRS network continues to track these arrays; additional stations plan to become operational in the near future. Analysis of LLR data provides information about the dynamics and structure of the Moon, its rate of rotation, and orbit, as well as gravitational physics and general relativity studies (Williams and Dickey, 2003).

LLR data are available in daily and monthly files within the normal point archive.