Tuesday, 4 May 2021


The first of a pair of research satellite reflectors—LAGEOS, from Laser Geometric Environmental Observation Survey, was launched on this day in 1976 (the partner mission was launched in 1992) placing the aluminium covered brass sphere, dimpled and looking like an oversized golf ball, in an extremely stable orbit. The enduring experiment is designed to aid with satellite orientation and terrestrial distances with the highest precision available, due to their regular circumnavigation of the Earth.  Approaching the period of a natural satellite, these artificial moons are expected to remain in orbit for over eight million years and contain a time-capsule, message in a bottle (see previously) for future Earth civilizations once it does re-enter the atmosphere, fast-forwarding continental drift to show their expected arrangement at that point in the future as compared to the present and page Pangaea accompanied by a binary calendar with the launch date starting as year zero.