The bathymetric data in SRTM30 PLUS stems from depth soundings (SONAR) and from satellite altimetry. Topographic images were collected using radar altimetry. The topography of the Moon has been measured with laser altimetry and stereo image analysis. She specializes in using gravity and laser altimetry measurements to determine interior structure and evolution. An outstanding new source of data had become available from satellite radar altimetry. Spaceborne platforms are also possible, see satellite laser altimetry. Navigation updates come from TRN Laser altimetry and star trackers after deorbit burn. With OSTM/Jason-2, ocean altimetry made the transition from research into operational mode. SARAL (or "Satellite with ARgos and AltiKa") is a cooperative altimetry technology mission. Bathymetry and satellite altimetry are two technologies working to close the gap. However, the MOLA instrument transmitted altimetry data only until June 2001. Despite the relatively flat landscape of Venus, the altimetry data also found large inclined plains. Its outline is clearly discernable only from altimetry data. The altimetry experiment of Magellan confirmed the general character of the landscape. This loss has been confirmed by laser altimetry.