NASA will be performing network maintenance on Wednesday, November 13, 2024, between 11:00 AM EST and 1:00 PM EST (16:00 to 18:00 UTC). There will be two periods of about five minutes of disruption. This will result in the unavailability of the CDDIS archive and the website. If you experience problems outside this window, contact support-cddis@nasa.gov.

close window
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.