SPACE.com: The Lunar Laser Ranging Experiment is the only moon investigation to continuously operate since the Apollo 11 mission.The experiment studies the Earth-Moon system and beams the data to labs around the world, including NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, Calif.Data from the ranging experiment has been used to learn—among other things—that the moon has a fluid core and is moving away from the Earth, and that Einstein’s Theory of Relativity is accurate.The instrument itself, called a lunar laser ranging reflector, was originally intended to accurately calculate the distance between the Earth and moon by measuring the round-trip time of a laser fired from Earth to a reflector on the instrument.
The finding that the Saturnian moon may host layers of icy slush instead of a global ocean could change how planetary scientists think about other icy moons as well.
Modeling the shapes of tree branches, neurons, and blood vessels is a thorny problem, but researchers have just discovered that much of the math has already been done.
January 29, 2026 12:52 PM
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