ESA Mar's Moon Phobos - Ancient Spacestation

Phobos is doomed. It is gradually spiralling towards Mars and eventually could slam into the planet’s surface, leaving a large crater as its parting gift.

Believe it or not, this discovery led to the USA’s President Eisenhower being briefed in 1960 that Phobos could be a space station launched by an advanced Martian civilisation.

At the time, calculations showed that the moon’s orbit was decaying at around 5 cm per year. Phobos is in an unusually low orbit around Mars, and so it was thought that this drag could be caused by the upper atmosphere of the planet.

Russian astrophysicist Iosif Samuilovich Shklovsky set about calculating whether the atmosphere could indeed be responsible. What he found surprised not only him, but many others too.

For the atmosphere to be responsible, Phobos would have to be hollow, like an Easter Egg. If the moon were solid rock, the atmosphere would have little effect.

A hollow moon would be susceptible because it contained so much less mass. But if the moon were hollow, it could not be a natural object.

Dr S. Fred Singer, special advisor to President Eisenhower on space developments, briefed the White House on this matter, emphasizing that Phobos could be an ancient abandoned spacecraft.

That's no moon, it's a... no wait, it is a moon.

Credits: ESA/ DLR/ FU Berlin (G. Neukum)