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  • Lunar Laser Ranging experiments - Wikipedia
    The distance can be calculated from the round-trip time of laser light pulses, travelling at the speed of light, which are reflected back to Earth by the Moon's surface or by one of several retroreflectors installed on the Moon
  • The Basics of Lunar Ranging
    Lunar laser ranging has been performed for the past 35 years, now reaching a precision of 2 centimeters APOLLO (the Apache Point Observatory Lunar Laser-ranging Operation) will improve this performance by at least a factor of ten
  • The Apollo Experiment That Keeps on Giving
    The Moon orbits Earth at an average distance of 239,000 miles (385,000 kilometers), but lunar laser ranging has accurately shown that the distance between the two increases by 1 5 inches (3 8 centimeters) a year
  • Lunar Locating at Light Speed: NASA’s Precision Laser . . . - SciTechDaily
    LOLA works by dispatching five laser beams toward the Moon and measuring how long it takes each one to bounce back (the quicker the light returns, the less distance between LOLA and the surface, and thus the higher the elevation in that area)
  • EclipseWise - Measuring the Moons Distance
    By beaming laser pulses at the reflector from Earth, scientists have been able to determine the round-trip travel time that gives the distance between the two bodies at any time to an accuracy of about 3 centimeters
  • APO, NMSU researchers detect new laser reflector on moon with amazing . . .
    Accurately measuring the distance to the moon through laser ranging experiments provides unique constraints on the moon’s orbit, its interior structure, and fundamental properties of gravity It also provides navigational benefits to upcoming spacecraft that will orbit or land on the moon
  • How to Measure the Earth–Moon Distance to the Last Micrometer
    Researchers can now measure the Earth–Moon distance with millimeter accuracy using laser pulses Switching to continuous laser operation could increase precision 10–100 times, allowing more stringent tests of general relativity and improving knowledge of the Moon’s internal structure
  • Lunar laser ranging: the millimeter challenge - IOPscience
    Lunar laser ranging has provided many of the best tests of gravitation since the first Apollo astronauts landed on the Moon The march to higher precision continues to this day, now entering the millimeter regime, and promising continued improvement in scientific results
  • Lunar Laser Ranging experiment - nuclear-power. com
    By measuring the round-trip time of the laser pulse, scientists can calculate the Earth-Moon distance with incredible accuracy, typically within a few centimeters To achieve such precision, LLR uses highly stable lasers, state-of-the-art timing systems, and advanced data processing techniques
  • We use lasers to keep track of the Moon - Big Think
    When we fire lasers from Earth and reflect them off of the installed reflectors on the Moon, we can actually measure the distance to the Moon with accuracy of just a few centimeters





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