Summary: Assuming no foreknowledge of its existence, can Elon Musk's Tesla Roadster be detected and categorised from Earth?

Bertrand Russell argued the following, an argument that is now known as Russell's Teapot (emphasis mine):

Many orthodox people speak as though it were the business of sceptics to disprove received dogmas rather than of dogmatists to prove them. This is, of course, a mistake. If I were to suggest that between the Earth and Mars there is a china teapot revolving about the sun in an elliptical orbit, nobody would be able to disprove my assertion provided I were careful to add that the teapot is too small to be revealed even by our most powerful telescopes.

Well now we have a midnight cherry red automobile, between Earth and Mars, in an elliptical orbit around the Sun.

Now assume that this civilisation we have falls. The knowledge of this automobile is lost. Then in some centuries/millennia later humanity has managed to work its way back to a level of technology comparable to what we have today.

Can this automobile then be detected by "our most powerful telescopes"?

I guess that we could detect it as an orbiting object; it is large enough to be found. Can you confirm or refute this guess?

And if the automobile can be found as an orbiting object, could it then be determined that this is no ordinary space rock, but that there is something very odd about it? That is to say: is it possible to do any kind of characterisation of the automobile that makes it stand out as an unusual space object. There is some uncertainty about the exact state of the automobile after such a long time, but there is no question that chemically and optically, this will be no space rock, even in several thousand years. The question is if we can detect that.

Digging some more I found about the (re)discovery of J002E3, which turned out to (probably) be the Apollo 12 Saturn-IVB upper stage. I quote from this paper (emphasis mine):

Additional spectral observations were completed in May 2003 at the Air Force Maui Optical Supercomputing (AMOS) site. Through the modeling of common spacecraft materials, the observations of J002E3 show a strong correlation of absorption features to a combination of human-made materials including white paint, black paint, and aluminum. Absorption features in the near IR show a strong correlation with paint containing a titanium-oxide semiconductor.

So, in short: could we do the same with this automobile and find that this is no ordinary space rock? How close would it have to be?

  • $\begingroup$ " could it then be determined that this is no ordinary space rock, but that there is something very odd about it?". This will be impossible to answer, since it is absolutely unknown what exposure to the cold of space will do to the car, especially the paint. if the paint stays intact and the object gets close enough to Earth, you might find out there is something odd about it, but this question invites pure speculation and should be left out. Its detectability is somewhat answerable, though. $\endgroup$
    – Polygnome
    Feb 7, 2018 at 10:07
  • $\begingroup$ @Polygnome Why should it be left out? The characterisation/categorisation of objects in space is of vital importance when it comes to space exploration. Just finding out "Oh, there is an object there" is of course interesting but the followup question "What are the characteristics of that object?" are just as important. And in the case of Russel's Teapot this question becomes essential: if we can only detect the teapot, but not determine that it is a teapot and not just some other object of the sort we expect to find in space, then we have no reason to assume that it is a teapot. $\endgroup$
    – MichaelK
    Feb 7, 2018 at 10:24
  • $\begingroup$ "What are the characteristics of that object right now" is a very different question (and probably answerable from an expert) then "What will the characteristics of that object be in a few millennia", which is pure speculation at this point. $\endgroup$
    – Polygnome
    Feb 7, 2018 at 10:27
  • 2
    $\begingroup$ @Polygnome Look, if you do not want to explore the subject of how we characterise space objects today — and put these in relation to the object in question: a car — then that is all fine, I am not demanding that you do. But now you are just trying to shut the question down on a formality. That is not fruitful. If you want to raise an issue that other answerers should consider then by all means leave a comment to that effect, saying "Do consider this factor of slight uncertainty". But to say that there is nothing but speculation here is only querulance and not helpful. Kindly stop that. $\endgroup$
    – MichaelK
    Feb 7, 2018 at 10:40
  • 2
    $\begingroup$ @Polygnome Let us continue this discussion in chat. $\endgroup$
    – MichaelK
    Feb 7, 2018 at 10:45

1 Answer 1


Can this automobile then be detected by "our most powerful telescopes"?


done :-)

This stuff transplanted from this answer.

A really cool GIF can be seen in the Space.com article Observatory Spots Elon Musk's Tesla Roadster Zooming Through Space (Video). It is over 7 MB so I can't add it here. However, here are ten frames from somewhere in the middle. Still, you should go see the whole thing.

enter image description here

DEMIOS image below, from here as also tweeted by Jonathan McDowell. The little dot near the center moving to the right and up is Roadster in reflected sunlight, probably mostly from the white FH 2nd stage still attached.

enter image description here

  • 3
    $\begingroup$ No, not "done". The Roadster is now outbound from Earth in present time, and so far following a known orbit. The question concerned once it is settled in a heliocentric orbit and has been there for a while, in the future, and it is not previously known that it is there. You also have not said whether it can be categorised or not. $\endgroup$
    – MichaelK
    Feb 9, 2018 at 11:47
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    $\begingroup$ @Casi I've added some pics, hope it's OK, feel free to rollback if not. $\endgroup$
    – uhoh
    Feb 10, 2018 at 16:36

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