I've mentioned before the possibility that there are abandoned extra-terrestrial facilities in the Solar-System. In 2014 in my article 'Atlas and Pan - Saturn's Generation Ships' (and in a recent follow-up 'Saturn's Unnatural History') I discussed the prospect that Saturn's unusual moons, Atlas, Pan, and Daphnis, could well be huge star ships that arrived in our star system millions of years ago.
Saturn and its moons seems to have been a system of great interest to extra-terrestrial visitors many millions of years ago.
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| Atlas, Daphnis and Pan: Saturn's unusual moons that may well be abandoned star ships. The amount of dust covering their surfaces suggests that they were abandoned many millions of years ago. |
This has had me thinking more and more about the smallest moons in the Solar-System. They are very hard to find, even when a space probe is in orbit around the host planet for many years. Very recently 12 new moons were discovered orbiting Jupiter. They are all very small, the largest no more than five kilometres across, and many are in a retrograde orbit. It's surprising that the Galileo spacecraft, which was in Jovian system for 8 years from 1995 to 2003, did not see those moons at all, but it's not surprising that they exist. Some of them may well have been placed there intentionally. Such moons would be ideal locations for clandestine colonies to hide, and for passive surveillance equipment to be placed to monitor our civilisation's development.
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| Calypso, one of the trojan moons that shares the orbit of Tethys, one of Saturn's moons. Calypso is just under 11 kilometres in length. It would make an ideal observational outpost. |
Four of Jupiter's other small moons that are also of interest are Telesto and Calypso (above), which are trojan bodies in the same orbit as that of the large moon Tethys, and Helene (below) and Polydeuces, both trojan bodies of the large moon Dione. It would be very easy for an advanced civilisation to conceal passive monitoring technology on such moons, and keep it hidden even after a technologically capable civilisation such as ours had made very close observations.
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| Helene, one of Dione's trojan companion moons |
Another example is Neptune's 14th moon, which was discovered in 2013 and recently named Hippocamp. It was found hidden in some of the Hubble Space Telescope's old data. At just under 35 kilometres in diameter, and dark in colour, it's no surprise that it was missed when Voyager 2 passed through Neptune's system in 1989. This small moon is another ideal example of an object large enough to sustain a colony, but small enough to be largely ignored.
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| An artist's impression of Hippocamp, the recently discovered moon of Neptune. At just under 35 kilometres in diameter it would be large enough to sustain a colony, or host a wealth of clandestine observational equipment, but it is small enough to go unnoticed, and to be largely ignored when eventually found. |
To understand why extra-terrestrial explorers would make use of such small moons, we only need to consider why we would use such moons in a similar situation. If humans found a star system with a life-bearing planet and we were able to visit that system we would want to learn as much about that life as possible. How advanced that life is would determine how we would monitor it without affecting its development.
If the life was primitive and consisted of nothing more than simple plant and animal life, such as during Earth's Ordovician period almost half a billion years ago, then probes in close orbit of the planet, and even airborne craft in its atmosphere, could be used. Surface missions could also be permitted (under very strictly adhered to planetary protection protocols) to gather samples. A permanent surface base would be possible.
If intelligent life was detected, but it was still in the early stages of building a civilisation such as bronze age societies, then close orbital probes would still be possible. Missions to the ground would be unwise anywhere but the most remote and underpopulated areas, but high altitude airborne flights could be done over populated areas. Such early civilisation would have little understanding of things beyond their immediate environment, but they would be curious, so great care would have to be taken not to be noticed.
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| Monitoring the development of a civilisation capable of producing art such as this from the bronze age in China more than 5,000 years ago would need to be done very carefully to avoid influencing their development |
If there was a more advanced civilisation at the level of a pre-industrial society where it is likely that scientific research into what lies beyond the atmosphere is being done, close orbital probes should be avoided as they could be seen. Monitoring should be done from high geostationary orbit. Research bases on the planet's moon(s) or nearby bodies should be used.
If there is a technologically advanced civilisation that is able to launch space missions, then it should be monitored well away from the planet. The small moons around that system's other planets would be ideal, as they will remain undetected for much longer, and are unlikely to come under close scrutiny even when discovered.
We are such a civilisation.
It's quite possible that we have been under surveillance by an extra-terrestrial civilisation for quite some time. And now, as we are sending spacecraft out to explore the Solar-System, that surveillance has retreated to distant small moons where we are unlikely to pay much attention. For that reason we should be paying extra attention to those moons. Many 'small moons' missions should be launched. And perhaps we should also launch probes to the outer Solar-System to an orbit beyond Neptune, where we can detect the possible transmissions that are being sent back to the home system of those that are monitoring us. Some of those probes should also orbit the sun well out of the normal planetary plane to ensure full coverage.
If we do all that we should have a good chance of discovering evidence that we are being watched.
And if we do make such a discovery, those watching will know about it. They may well decide that it's time to make direct contact.
