Possible Underground Structure On The Satellite Of The Planet Mars, Phobos

It has previously been proposed that Phobos is an artificial object launched by a hypothetical civilization that once inhabited Mars.

From Wikimedia Common

In 1945, the American astronomer Bevan Sharpless detected an acceleration of Phobos that could not be explained as a result of a disturbance in the thin Martian atmosphere.

The information did not receive much attention until it was picked up by Soviet astrophysicist Iósif Shklovsky, who in 1959 proposed that the satellite might be a…