On May 4, 1976, a spacecraft resembling a disco ball entered orbit almost 3,700 miles (6,000 kilometers) above Earth. This shiny, two‑foot‑wide (60‑centimeter) sphere called the Laser Geodynamics Satellite, or LAGEOS, is covered with 426 retroreflectors—small mirrored prisms designed to bounce laser light directly back to where it came from. Beneath its aluminum exterior sits […]
Posted on
May 4, 2026
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