Xenology: An Introduction to the Scientific Study of Extraterrestrial Life, Intelligence, and Civilization

First Edition

© 1975-1979, 2008 Robert A. Freitas Jr. All Rights Reserved.

Robert A. Freitas Jr., Xenology: An Introduction to the Scientific Study of Extraterrestrial Life, Intelligence, and Civilization, First Edition, Xenology Research Institute, Sacramento, CA, 1979; http://www.xenology.info/Xeno.htm


24.3.3 The Nature of Alien Artifacts

Bracewell probes are just one kind of nonhuman artifact we may discover in our own solar system.3152 Foster,1136 Macvey,2724 and others have described a number of alternative possibilities:

Space Laboratories -- may be crewed by biological lifeforms, cyborgs, automata, robots, or other mechanical devices.3279 May also exist as wrecks, hulks, or otherwise in derelict condition.

Repeater Stations -- automatic and designed to operate for long periods of time unattended. Capable of receiving, sifting, organizing, and retransmitting signals across interstellar distances. May be part of a galactic communications network, relaying messages using radio waves, x-rays, neutrinos, tachyons, or whatever.3418

Telemetry Stations -- designed to observe, detect, and record changing local environmental characteristics., and perhaps to transmit these data, together with its own operational status, periodically to some agent or agency located outside the solar system. Interactive functions are not ruled out, but basic mission is observation.3293

Marker Buoys -- transmits navigational beams which future starships from the same visiting alien civilization can use to home in on Sol. Another function may be to tag fuel dumps, valuable local mineral deposits, databank storage facilities, unusual objects of special or potential interest, or caches of essential equipment left behind by a former expedition.

Monuments and Edifices -- serving to record or to symbolically identify past expeditions to a site; grave markers for deceased, unborn, or hibernating alien astronauts; nonfunctional obelisks or plaques.3256 Might also serve as informational or data repositories such as a Saunders Databank,2611 Edie’s organic message carriers in meteorites or comets,150,154 or something like the "Extraterrestrial Message Block" on display at the National Air and Space Museum in Washington, D.C.3157

Tools and Implements -- all sorts of equipment ranging from lost screwdrivers and wrenches (or the alien equivalent) to cast-off electronic components, sophisticated recording or sensing instruments, abandoned computers, and unserviceable nuclear reactors.

Refuse or Debris -- blocks or shards of metal, ceramic, or plastic scrap and other waste materials clearly of extraterrestrial manufacture or origin; undecomposed biological wastes or debris; deposits of industrial tailings; sites of chemical or radioactive contamination; alien corpses in spacesuits.3294

Environmental Evidence -- unnatural rearrangement of surface terrain; fused rock; inexplicable radioactive "hot spots"; severe paleomagnetic or geomagnetic anomalies; destruction of planetary bodies (our Asteroid Belt?); planetary orbital anomalies (our Pluto?); unusual geological or planetological phenomena (Saturn’s rings?). Another suggestion is that our DNA code may itself be an alien message left behind on a lifeless Earth eons ago by visiting ETs. Its ability to survive and to reproduce seems a perfect solution to the problem of durability over geological timescales.3178,2611

Are there any preferred locations in the Solar System when alien artifacts are most likely to be found? Many writers have suggested that there are four distinct places where physical evidence of the past presence of ETs may be found:

1. Objects in transient hyperbolic orbits around the Sun. (Single pass through our Solar System, very difficult to detect)

2. Objects in permanent orbit around Sol. (Orbit may be highly eccentric, or perfectly circular. Difficult to detect, but we have lots of time to look.)

3. Objects in orbit around planets, moons, or asteroids.

4. Objects located on or below the surfaces of planets, moons, or asteroids.

It would seem that (3) and (4) would offer the best prospects for easy detection, We have already mentioned (3) in connection with Bracewell probes. These devices might be parked in a stable synchronous orbit or in the Trojan Points if there’s a large natural satellite nearby. Unusual moons such as Iapetus or Titan of Saturn, Triton of Neptune, and Charon of Pluto similarly may be tagged with orbiting artifacts.

What about possibility (4), surface artifacts? The majority of planetary surfaces in our Solar System are unsuitable for the long-term preservation of objects soft-landed from space. Only a very small proportion of the total surface area of our System has any degree of permanence at all, and the forces of erosion which occur on any world with an appreciable atmosphere (or winds) or widespread geological plate tectonic (or volcanic) activity suffice to rule out many major planetary bodies. We must therefore exclude Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. This leaves the surfaces of Mercury, Pluto, most of the moons of planets, and all of the asteroids. Table 24.5 below shows the total "stabilized" surface area available for extremely long-tern storage of alien artifacts in our Solar System.


Table 24.5 Total "Stabilized" Surface Area Available in Solar System 
for Long-Term Deposition of Alien Artifacts (modified from Foster1136)
Celestial Body
Available "Stabilized" Surface Area
of Total
Satellites of Jupiter
2.0 1014
Satellites of Saturn
9.1 1013
7.5 1013
Satellites of Neptune
4.3 1013
3.8 1013
2.0 1013
Satellites of Uranus
1.0 1013
6.0 1012
Charon (Pluto’s moon)
2.0 1012


What if future astronauts from Earth stumble upon an artificial device or artifact clearly of alien manufacture, in the Solar System or elsewhere? Do we have the right to tamper with, and possibly destroy, property belonging to ETs? Or can we claim eminent domain or "salvage rights" and thus convert it to our own use, however we see fit? (After all, it is intruding in our solar system -- can’t we do what we like with it?) What if we mistakenly activate the mechanism, or use it incorrectly, and it causes us serious harm? Can we demand reparations from the extraterrestrial race that left it here, under some notion of "attractive nuisance"?

Certainly the aliens who planted the artifact are technologically far in advance of ourselves, assuming we find it in our Solar System before we have achieved interstellar travel capabilities. The mere fact that we have found the object thus suggests either that it was intended to be found or that it was not intended to be hidden (the ETs don’t care if we find their sandwich wrappers). Technically advanced aliens should be able adequately to hide an artifact from querulous human explorers. So such machines or devices probably will not be equipped with "death rays" or similar unpleasantries to ward off intruders. If intended to be found, starprobes ought not be designed to be tamper-proof by curious sentients. In fact, in the interests of interstellar amity, the alien artifact should clearly demonstrate that it has nothing to hide (except the location of its home star); that it is a messenger of information, peace, and goodwill; and that it is not to be feared, suspected, or avoided. It should be easily disassemblable. The sacrifice even of a complex and expensive machine may well be worth the avoidance of interstellar hostilities between races.

If probes or artifacts are discovered by human astronauts, the event represents a variety of first contact and a tremendous opportunity for communication and technical progress. Duncan Lunan, summarizing the conclusions of an ASTRA study entitled "Man and the Stars,"1001 offers the following practical advice for handling alien devices of various types:

If [astronauts] stumbled on something accidentally, perhaps they should leave it alone until experts get there, but that is not practicable on interplanetary or interstellar missions. In the interplanetary situation, they should send data back to Earth but not touch, in the first instance -- the approach from there will be determined by what the thing appears to be and whether it still appears active. The next stage would be to try radio and light signals on it, with caution if we don’t know what it is: we may get a reaction as well as data. Before any close approach there would have to be tests for radioactivity etc., even if the object appears inactive.

A small enough object could be brought back to Earth for study, but that decision requires great caution -- the thing could be a container for radioactive or biological waste, or a weapon platform. It is entirely possible that something dumped, or launched, by someone else could be dangerous to us. If brought back for study, the object should be placed on the Moon or in Earth orbit rather than landed. If it is small enough to be brought back the odds are that we detected it by its emissions, therefore it is probably still active. We should be prepared for this situation to turn into a true Contact -- the object could be one of Professor Nonweiler’s hypothetical cryo-bio-packages, or an escape capsule with the occupant in suspended animation.

For a large, immobile object, detected for instance on a planetary surface by photographic survey, we would have to establish on-site investigation facilities. Even so the first checks should probably be made by Lunokhod-type vehicles, because of a reaction when we begin active study with radio, x-rays, etc. How far would we go in active examination -- would we take such a thing apart at any stage? Arthur C. Clarke’s "Sentinel" was meant to be broken, so that its makers would know intelligence here had mastered spaceflight and atomic energy. The black monolith, the version of the device depicted in 2001: A Space Odyssey, had only to be dug up: as soon as sunlight struck it, it was activated and began its study of us. In the former case, the destruction of the pyramid was to bring "Them" back; in the latter, where the monoliths were supposedly responsible for the development of our intelligence, we were directed to the third monolith which delivered the next part of the programmed learning course. The object we find in real life, however, may be more functional. If it is a navigational beacon, for example, interfering with it may bring a repair crew rather than a Contact team.

If we were leaving or launching an object that was intended to be found, we would put information or instructions on the outside {e.g., the Pioneer 10 plaque}. So if the object we find doesn’t have any, we should treat it with caution. But the absence of instructions may just mean that the makers did not expect intelligence to find it -- we don’t put external data on our interplanetary probes, arid probes from intelligence elsewhere in the Solar System (e.g. Jovian or Venus life) might be harmless even if unmarked. An intelligence from elsewhere, exploring the System before our time and anticipating the development of one or more intelligent lifeforms here, might be expected to leave unambiguous message-artifacts like Professor Bracewell’s hypothetical repeaters, and plant them in as many places as possible.1001


Last updated on 6 December 2008