Contents

1. Meanderings
2. Exoarcheology 101
3. Bookends

1. Meanderings

One thing I couldn't be is someone who builds experiments to send to other worlds. It's the suspense and uncertainty that would get to me. Consider the European Space Agency probe Mars Express, due to blast off from Baikonur Cosmodrome on June 2 for arrival in Martian orbit on December 26. It carries the miniature lander Beagle 2, which is scheduled to make planetfall in the New Year and sniff the Martian air and subsurface soil for traces of anything biological. How well would you be sleeping right now if you were one of the researchers involved in that project? First your delicate apparatus, which took years to design, build, and test, has to shake, rattle, and roll its way into orbit on top of a chemical bomb. (There's no backup mission.) Then you have to hope that the engine burn goes well to get Mars Express on its way to the Red Planet. And that nothing goes wrong along the way. And that Mars orbit insertion goes to plan. And that the parachute deploys, and that the hit, bounce, and roll airbag technology gets your instruments onto the surface in one piece and the right way up. If you're still in business at this stage, you're just at the start of worrying if your instruments will turn on and do what they're supposed to. No, I don't think I could stand the strain. On the other hand, if Beagle 2 does arrive safely on Isidis Planitia and carries out its tests without a hitch, it just might pull off the achievement of the millennium – detecting the first signs of life beyond Earth. No other planetary mission on the short-range radar carries a specific biological package: Beagle is our best hope of an immediate breakthrough.

2. Exoarcheology 101

Just as exobiology is the study of life beyond Earth, so exoarchaeology is the study of the traces, relics, and artifacts of past extraterrestrial intelligence or cultures. (There's a subtle distinction between "astro-", as in astrobiology, and "exo-", as in exobiology, in that "exo-" means outside and therefore includes everything except the Earth, whereas "astro-" means related to the stars, and thus implies everything including the Earth. By this reckoning, astrobiology is the universal science of life, inclusive of terrestrial biology, whereas exobiology is the science of strictly alien life). OK, so exoarchaeology is the science of ancient extraterrestrial artifacts. What extraterrestrial artifacts you may well ask? Well, the absence-to-date of confirmed extraterrestrial life hasn't stopped exobiology from getting a toehold in mainstream science on the basis that we may well soon make that vital breakthrough. So, it's perhaps not too early to get cracking on a science of exoarchaeology on the grounds that, sooner of later, we're going to come across some signs of past exo-cultures. Let's at least start to put the methodology in place, imagine what kind of alien artifacts might turn up, and consider some of the places of special interest for off-world digs.

You may think this is starting to sound a bit Erich-von-Danikenish. Von Daniken, in case you've been in stasis for the past three decades or so, sold vast quantities of his "Chariots of the Gods" and its sequels and brought to wide public attention the hypothesis of "ancient astronauts" – the idea that advanced aliens visited the Earth thousands of years ago and influenced our own ancient cultures. Perfectly plausible, of course. Unfortunately, von Daniken relies more on tabloid journalism and unspecified sources than on anything remotely resembling true scholarship. What's more, I don't think many people realize that he borrowed most of his ideas from genuine archaeologists and ethnologists who had raised the possibility of extraterrestrial relics on Earth in the 1940s and '50s. Prominent among these was the French archaeologist Henri Lhote who, in his book "The Search for the Tassili Frescoes", published just after World War II, pointed to some curious frescoes from Tassili-n-ajjer in the central Sahara, dating back several millennia B.C. His reproductions of what he called "Jabbaren", the great Martian god, and other strange figures, are striking and superficially mystifying, but have since been adequately accounted for, more mundanely, in terms of ordinary humans wearing ceremonial costumes and masks. Anyone looking for a good, sound introduction to early theories (and rebuttals) of exoarchaeology should check out chapter 33 of Sagan and Shklovskii's 1966 classic "Intelligent Life in the Universe." You might also like to browse a few of my own on-line encyclopedia articles, including paleocontact hypothesis, Matest Agrest, Mikhail Agrest, Sirius, mystery of red color, and the various links from these.

Exoarchaeology has roots stretching back before the mid-twentieth century. Percival Lowell's canals, had they been real, could easily have been the relic of a dead or dying Martian civilization. Earlier, Franz Gruithuisen thought he'd seen signs of a civilization on the Moon (not to mention Venus). And, in fiction, George Griffith and others were charting out the possibilities for finding monuments of long-ago alien races on the Moon, Mars, and elsewhere.

Some people enjoy scouring NASA images of Mars, taken by Mars Global Surveyor and the 2001 Odyssey probe, in the hope of spotting signs of things that look artificial – pyramids, the infamous "face," even entire cities. It's good to be on the lookout for such things, and who knows? But it's also a very dodgy pastime if you're not a planetary geologist, fraught with Lowellian possibilities of glimpsing patterns at the edge of resolution and generally convincing yourself that shapes and collections of objects that look somewhat regular in layout may be artificial when, in fact, they have a perfectly innocent, natural explanation. The key in exoarchaeology, as in all science, is to start out with the simplest, least spectacular explanations. Avoid speculating about anything more esoteric until you've totally excluded the mundane. As Sherlock Holme's said in The Blanched Soldier: "When you have eliminated all which is impossible, then whatever remains, however improbable, must be the truth." The most important word here is "when"!

Of course, there are whole websites devoted to arguing the case for long-lost civilizations on the deserts of Mars, complete with heavily re-processed photos that owe more to the imagination of contemporary humans than to the ingenuity of extraterrestrial architects and engineers. Yet there's also some serious and well-considered work being done in the field of what has been called SETA (Search for Extraterrestrial Artifacts). Mark Carlotto's expert analyses of the Cydonia site (go here) are worth reading, even if (as in my own case) you don't necessarily agree with his conclusions. Similarly, the Ukrainian radio astronomer Alexey Arkhipov has made some important contributions to exoarchaeology in the context of the Moon. See, for example, here.

Anyone who ventures into this subject risks being tarred with the same brush as that small army of amateur armchair enthusiasts who see an alien hand at work in every anomalous planetary feature or trick of the light. But the fact is that exoarchaeology is not an outlandish possibility. On the contrary, recent developments in astrobiology have increased the chances that we've been visited in the past or that other traces of alien intelligence may be waiting to be found elsewhere in the Solar System. Over the next couple of decades, there are plans by NASA and the European Space Agency to launch a series of increasingly powerful instruments whose aim will be to detect and then probe Earthlike extrasolar planets. Ultimately, if things work out, we should be able to surmise the presence of life on worlds going around other stars and even get some idea of its stage of evolution. If advanced technological races are out there, the Earth may have been identified as a bearer of advanced (i.e. multicellular) life millions of years ago. What would be more logical than that those watchers among the stars should then dispatch probes or even survey parties to reconnoiter the Solar System and monitor the progress of life on the third (and maybe fourth) planet? Watch this space!

3. Bookends

You can get a sneak preview of my next book, "The Universal Book of Astronomy," including the cover art, at this John Wiley catalog page. Publication date is October 2003. This is the companion to "The Complete Book of Spaceflight" which came out at the end of last year. Fall 2004 will see the publication of the third in my A-Z series, on recreational math. I'm just starting research for another Wiley book – on Teleportation. So, if you have any bright ideas about quantum entanglement or other issues to do with beaming objects around, please get in touch!


Until next time,
Best wishes,
David Darling