Post by Chicago Astronomer - Astro Joe on May 17, 2006 23:13:47 GMT -6
Looking for aliens on the Moon
When astronauts return to the Moon, they should keep their eyes peeled for extraterrestrial artefacts – pieces of technology from alien civilisations that have wound up on the lunar surface either by chance or design.
So says Ian Crawford, a researcher from University of London’s Birkbeck College in the UK. He told a SETI specialist meeting of the Royal Astronomical Society (RAS) in London last week that although he considers such a find a long-shot, it is definitely worth bearing in mind.
“This is not a primary reason to go back to the Moon – there are very strong scientific reasons for going back. But if we go back to the Moon in the next 20 or 30 years, then amongst those things we might like to keep our eyes open for are alien artefacts,” Crawford told New Scientist.
The focus of the RAS discussion was the history and status of the search for extraterrestrial intelligence – an endeavour that has largely relied so far on large radio telescopes listening for electromagnetic signals from other technological civilisations.
Little additional cost
Crawford thinks scientists will be keen for the next lunar astronauts to sift through the lunar soil in greater quantities and in more detail was possible during the Apollo era. So there would be little additional cost to remain open to the idea that alien material may exist within those upper metres of the moon’s regolith.
Seth Shostak, senior astronomer at the SETI Institute in Mountain View, California, says the possibility of such an interesting payoff for little additional cost makes the idea of looking for artefacts worth considering.
"On the Moon, I think it’s certainly worthwhile taking a couple hundred square feet or so of material and looking it over," he says. But SETI researchers "probably wouldn't bet their mortgages on finding anything".
Message in a bottle
Looking for small artefacts, or even probes or time capsules, in our solar system is not a new idea in the SETI community, Shostak notes. Indeed, our own civilisation has already taken this approach several times.
NASA's Pioneer 10 and 11 spacecraft carry metal plaques showing the spacecraft's time and place of origin. And the Voyager 1 and 2 probes carry gold-plated records (pictured) bearing messages, images and sounds depicting life on Earth for any extraterrestrials who might encounter them thousands of years from now.
In 2004, an engineer and a physicist published a paper in Nature suggesting that if extraterrestrials were not in a hurry, their best shot at making contact with other civilisations would not be with radio waves, but with an interstellar message in a bottle – a physical artefact to tell other intelligent life forms something about their existence.
Crawford says the moon would be a good target for such "inscribed matter", given its lack of geologic activity and airless environment. But if an intentional targeting of a relatively small body sounds a little too like 2001: A Space Odyssey, he says there is also a possibility first brought to his attention by a 1998 paper by Ukrainian astronomer Alexy Arkhipov.
This suggests that if enough space faring societies have existed, even if they never travelled beyond their own planetary systems, they may have produced enough space debris to make it possible that micron-sized particles could have reached our own solar system. And Crawford says such tiny material could have fallen to the moon, remaining there within the top 10 or 15 metres of regolith.
Excruciating detail
But several lunar experts describe the prospect of finding extraterrestrial artefacts on the moon as "far-fetched". Gary Lofgren, lunar curator in charge of the scientific preservation of the Apollo lunar samples at the Johnson Space Center in Houston says even if such extraterrestrial micron-sized particles are there, it would be incredibly difficult to find them, requiring special instrumentation that has never been sent to space before.
Apollo astronauts brought a total of 842 pounds (382 kilograms) of lunar material to Earth and researchers are still studying the samples today. Lofgren says: "People have gone through the samples in excruciating detail and haven't found anything that would suggest extraterrestrial activity."
In fact, he says, scientists have even been surprised by how little of the material has been assigned an origin off the moon – rocks from Earth or Mars thrown up by meteorite impacts, for example.
Still, Lofgren says, scientists will be eager to study new samples from the Moon, noting that the Apollo samples only cover six sites clustered around the equator. And he says, a discovery of material that cannot be explained by an origin and evolution within our solar system "would be an incredible find".
Scott Hubbard, former director of NASA's Ames Research Center and now a SETI Institute researcher says: "While nothing is impossible, I find the payoff from seeking a cometary in-fall in the Moon's permanently shadowed craters much more compelling than extraterrestrial civilisation artefacts."
Source here: www.newscientistspace.com/article.ns?id=dn9173&feedId=space_rss20
While emitting an intense high-pitched eardrum piercing sound, the monolith completely shattered, scattering about 260 microscopic pieces of itself across every square kilometer of the lunar surface. However, if an enterprising person were to work very hard, he may be able to collect and reassemble the bits for display in his own living room. Won’t his friends be in awe! 
