Caelum Incognitum — The interactive encyclopedia of ufology
Hollow Moon
Hypotheses & theories
A hypothesis advanced in 1970 in the Soviet magazine “Sputnik” by Mikhail Vasin and Alexander Shcherbakov: the Moon would be a hollow artificial spaceship. It is contradicted by the Apollo seismometers, the Moon’s measured mass and density, and GRAIL gravimetry, which show a differentiated rocky body.