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Probe flies by ‘alien space station’
A European probe is tonight skimming past a moon that was once thought to be an alien spacecraft. Mars Express will swoop less than 42 miles over Phobos, one of two natural satellites orbiting the red planet.
The flypast – the closest ever – will allow scientists to measure deep inside the 17 mile wide, potato-shaped moon to see just what it is made of.
Phobos, thought to be an asteroid captured by Mars’s gravity, has an unusual low orbit that is taking it spiralling slowly towards an impact.
According to the European Space Agency’s Phobos blog, that led to US President Dwight Eisenhower being briefed in 1960 that it could be a space station launched by an advanced Martian civilisation. (NB: The ESA blog entry has now been removed).
Scientists at the time thought that drag from the atmosphere was causing Phobos to sink in its orbit by around two inches a year – and for that to happen, some said it had to be hollow like an Easter egg.
A Russian suggestion was apparently that the moon could not therefore be a natural object and might be an ancient abandoned spacecraft. Fred Singer, a special advisor on space to the White House, was said by ESA to have passed this information on to the President. However, noted atmospheric physicist Professor Singer, who is now 85, tells us he did no such thing and in fact, he was instrumental, with Ernst Opik (see below), in coming up with the correct explanation for Phobos’s descent – a deceleration caused by Mars’s tidal pull.
There will be no photos from the close encounter because Mars Express will be on Phobos’s night side. The image here was taken on a previous flyby.
Mars scientists will probe Phobos’s real interior by listening to its gravitational effect on a radio signal from their spacecraft during the flyby. Mars also has a smaller nine mile wide moon called Deimos.
LibDem MP Lembit Opik’s grandfather Ernst Opik first noted (with Singer) the correct reason for Phobos’s strange orbit in 1964. The moon must have an irregular shape and the pull of Mars’s gravity created a tidal force that robbed it of energy.
As Star Wars fans might say: “That’s no space station … it’s a moon!”
Note added on March 9: I am very happy to edit this story to make clear the correct nature of Professor Singer’s involvement in solving this remarkable riddle from the history of Mars exploration.
Photo: NASA.
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March 8, 2010 • 11:31 pm
Mr. Sutherland:
Despite the interest in the examination of the moon Phobos, your article contains factual errors which are not only incorrect but, unfortunately, defamatory.
Dr. Fred Singer never briefed Eisenhower on the topic, nor suggested that the moon was either "hollow" or an "alien spaceship" — a complete fantasy on your part!
The facts are that it was Russian astronomer Shklovsky who suggested that Phobos was hollow (like a balloon) — and artificial.
Opik and Dr. Singer suggested the correct explanation for the observed Phobos orbit changes: tidal deceleration. Dr. Singer followed up with calculations, eventually published in Geophysical Journal of Royal Astronomical Society in 1968.
Please issue a correction and retraction of this false claim immediately.
March 8, 2010 • 11:43 pm
What is your source for "Dr Fred Singer, special advisor to the White House, told the President that the moon could not therefore be a natural object and might be an ancient abandoned spacecraft." I cannot find an authoritative source for this, which may explain why SCIENTIFIC AMERICAN has removed your post from their site.
March 9, 2010 • 12:07 am
Can you provide a source for the claim that Dr. S. Fred Singer ever claimed that Phobos is artificial or hollow or that he ever so advised President Eisenhower?
March 9, 2010 • 4:05 am
Thanks for the interest.My source was the official blog of the European Space Agency which operates the Mars Express probe: http://webservices.esa.int/blog/post/7/1020
March 9, 2010 • 4:51 am
I have now edited the story to make clear Professor Singer's role in the Phobos riddle, and to give him due credit for helping produce the true explanation for the moon's behaviour.
March 10, 2010 • 12:03 pm
Dr Singer has also contributed the following comments:
Some corrections, if I may:
1. Although my original publication in Geophys J of the Royal Astron Soc [1968] did suggest that both Phobos and Deimos might be captured asteroids (based on the similarity of their initial orbits — both parabolic), I no longer hold this view. I know of no physical mechanism ( their masses are too small) and the probability is vanishingly small.
I regret that I have never published a formal retraction and that my initial suggestion has apparently acquired wide currency.
Pls note that I still believe that the Moon was captured and that the widely popular 'impact hypothesis'.has problems with the laws of physics besides being improbable. I hope to publish all this before long.
2. The tidal deceleration of Phobos does not depend on its shape; it would work on a perfect sphere. The tidal deformations are raised on Mars, not on Phobos. Its actual non-spherical shape simply determines its orientation (not its orbit)
3. The origin of Ph and D is still a mystery. I have eliminated the possibility of co-formation with Mars on physical grounds. I do have a hypothesis but it is very ad hoc; My recent presentation at a CalTech conference on Mars (published as an abstract) did not elicit much reaction.
There is also the question of why Ph and D have such a different appearance. It may have to do with their different orbits.
Sincerely, SFS