How could I justify that ancient humans ruins have not been discovered?

Question

Scenario:

Earth's history is 100% equal to reality . It’s the year 2040. First interplanetary cities with 3% total population of mankind.

200 million years ago humans appeared on Venus, developing into a greatly advanced civilization spanning multiple planets (divided into multiple nations) until a catastrophic war killed most of them (rendering Venus hostile to life and destroying all major habitats and cities). The survivors (about 200k people) tasked an AI to make Earth habitable and then went into stasis chambers (my equivalent of cryogenic technology) in which some of them remain until today. Once Earth was habitable the majority of survivors migrated there and became the beginning of modern-day mankind. Then the AI shut itself down.

About 20k of those 200k stasis chambers survived (they are different from those survivors used to establish the human population on Earth). Prior to their emergence from stasis in 2040, the chambers were floating in space.

Question: If the ruins are still standing and technically visible, why they haven’t been seen by modern people (by using telescopes or similar)? What would be the reason for modern scientists' inability to discover any remains (broken ships, space stations, etc.)?

Note: the ruins are all over the solar system. In modern times there are still remaining ruins (though most don't need to work) and people in stasis that in theory could be awakened

Answer 1

We still haven't been able to watch in the good spots

Except for the planets where we have sent probes, we don't know have that big resolution of the surface of the objects in the Solar System (for instance, there is still some debate about the effective shape of Oumaouma).
The places where we were able to map in high resolution the surface and we can rule out the existence of some big or medium sized surface structures are (if I remember well):

• Mercury
• Moon
• Mars
• Ceres
• Eros
• Pluto and Charon (not 100% of the surface)

The satellites of Jupiter and Saturn were mapped at different resolutions, but, for instance Europa is mainly mapped at 1km resolution, so if the ruins were rare and far apart, it would still be difficult to have an image of them at the current level of technology and exploration of the solar system.

About the mentioned planets, they would be the places where the population density was higher, so the places where the war likely brought the most destruction: it is safe to assume that whatever structures existed there would have been completely destroyed during the war (and, particularly on Earth, erosion did the rest).

About the chambers, if they are some meters of size, it is likely that we haven't been able to see them (or, if we have, we haven't been able to realize they are artificial objects, since in many cases we were able to only measure the brightness): from the wikipedia page about near Earth objects

The number of asteroids brighter than H = 25, which corresponds to about 40 m (130 ft) in diameter, is estimated at about 840,000±23,000—of which about 1.3 percent had been discovered by February 2016;

And it would be even less if these chambers were placed on a far from Earth orbit.

Answer 2

Geology and nature

The disappearance of most spaceships, ruins and technology is easy. Earth is relatively benign compared to many other regions of the solar system. In the timeframe you're talking a great many things can and will happen. Sattelites will crash or be trown out of the solar system. Ruins will be eroded, cities will crumble and little will be present to show that there was a civilization at all. Even things like plastics, which few organisms and processes can destroy, will mostly be reduced in such societies and the remainder can be difficult to pick up on unless you're physically there with equipmemt. It's more difficult to have things survive a million or 50 million years than have anything left standing. Seeding ships and such can destroy themselves when their task is finished into pieces small enough that they'll be eroded long before people can detect them.

The only problem is the cryochambers. If you want them to survive, you either need a super stable area or constant maintenance, preferably both. Deep underground or the sea is a good possibility, as long as it's stable enough. Even then many will probably not survive due to random movements of the soil.

An alternative is hiding cryo in the astroid belt, inside the astroids. They aren't stable, as in the last 100 million years the astroid belt has been reduced with more than 99% thanks to random collisions, but it'll be difficult to detect with modern equipment.

Finally you can hide them outside the solar system. They might be small enough and quickly far enough not to be detected or thought of anything else than random debris, if detected at all. It is still not fully safe, but it can explain why only 20 million survive.

Answer 3

Being buried under Antarctica or under the ocean bed seems as good a place as any to not be found.

This holds true on other planets too. Things tend to get buried after 200 million years anywhere there is weather. And if there's no weather, there's probably a lot of meteorite impacts so you would probably want to bury it yourself anyways. You're not going to see any of that through a telescope.

200 million years is also plenty of time for space station in orbit around a planet to deorbit.

Answer 4

They landed 200 million years ago on a planet with nothing to support their tech.

The best they could was to cannibalize their ships and reuse as much as possible for their purpose: why do you keep a space ship when you need a blade to kill some animal and reach tomorrow? You tear it to pieces and reuse it, and since of course you have nothing to maintain the tools you make, they will be tore down to dust and rust.

If anything can be found it won't be ships, it will be shavings and fragments.

Answer 5

They were placed at the subduction zones of fault lines, and thus subsequently destroyed as they were buried in magma. 200 million years is more than enough time to subduct anything placed in these areas and leave virtually no trace.

So how were they ultimately found in 2040? Perhaps they contained rare elements not typically found in large supply on Earth, and these elements were detected in the discharge from nearby volcanoes? Maybe one or two of them wasn't quite close enough to the subduction zone to be pulled down, but it wouldn't be discovered so easily because it's still buried under the sea floor at the bottom of the deepest trenches in the ocean. Possibly some future deep-sea construction project unearths some surviving relics. Maybe some ancient sea creature found one and dragged it away from the subduction zone before deciding it wasn't edible. There's any number of possibilities.

Answer 6

Underground

They built pretty much everything under the surface. While you've stated that Venus was habitable, the other planetary bodies would not be (with Earth being disqualified by your statement that they needed to terraform it).

Safety from the natural dangers of radiation and meteor strikes, in addition to the dangers from interplanetary warfare, resulted in subterranean communities.

Similarly, any orbital habitats would have a layer of rocks and ice surrounding them, giving them the appearance of asteroids.

One large issue that you may need to address, is the dangers of long term cryopreservation. Even if you are perfectly shielded from outside dangers, the radioactivity given off by your own body will end up doing fatal damage. This would be over a timespan of a century or so, so a timeframe of millions of years would require something to counter that.

Answer 7

Partial Answer:

Not sure if partial answer works the same way here as over on puzzling, but here we go...

ON VENUS (not trying to explain why there is nothing, anywhere in the solar system, as it's generally answered by others / I agree lets hand wave 200 million years is plenty of time as described in other answers - probably is, but no one is really supporting) specifically the majority of the world is an ocean, but it wasn't always. Venus used to be much more earth like with continents spread across it - the original humanoid inhabitants were unable to control sea level rise, or adapt to it, and were pushed to relatively last minute escape measures - most of the planet Venus is well developed by our standards, i.e. like greater Los Angeles across the planet, but taller skyscrapers in many locations. It's still there to this day, but it's all underwater now. The Earthen myth of Atlantis actually stems from the civilization on Venus, not anything on Earth.

At least one source for the whole "it's all covered in water now" claim: https://earthsky.org/space/venus-map-with-oceans-on-surface-terraforming#:~:text=And%20what%20does%20it%20show,and%20lows%20on%20Venus%20surface(I had to remove a "'" after Venus for the link to work correctly on SE)

And while the time frames are a little off, Wikipedia claims habitability until 700 million years ago-https://en.wikipedia.org/wiki/Life_on_Venus#:~:text=Recent%20studies%20from%20September%202019,to%20750%20million%20years%20ago. -doesn't really establish massive sea level rise that hide a far advanced civilization, but we also only have scans through heavy clouds so imagination wins here

Might be a stretched for science based? Not sure, but it all kind of is, so hope this helps!

Answer 8

After having been in the cosmos of the solar system for nearly 200 million years, the stasis chambers accumulated dust and were impacted by asteroids and comets and are themselves covered in the collision detritus and they look like any other asteroid or comet in the solar system.

Have a closer look at Ceres, Vesta, Triton. There will be other that just haven't been noticed.