As spotlighted on August 12 ("Laser ranging and LRO") NASA's Goddard Space Flight Center is using the Lunar Reconnaissance Orbiter laser altimeter ("LOLA") for more than just determining the distance and anatomy of the lunar surface. Routed through the vehicle's high-gain antenna, LOLA is also being used to make more accurate measurements of the distance between its transient location in lunar orbit and fixed points on Earth. The method used for "reflecting" laser light pulses from Earth is not passive, as with decades of counting photons being reflected back to Earth by the laser "retro-reflector" mirror arrays left on the Moon by Apollo. Instead, LRO collects photons after a one-way trip, at the vehicle, and then tags the data before returning detailed information back to Earth. Eventually, this method may aid in resolving some hairy cosmic questions, such as whether expansion of the Cosmos varies locally from what is observed at great distances. On July 12, the United Kingdom's Space Geodesy Facility located LRO within 10 centimeters, using a 13 Hz timed laser pulse from its SLR . The UK's SGF is managed by the National Environmental Research Council, which announced the results on their website "Planet Earth."
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