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by marcyb5st 1742 days ago
For this approach I don't know. It's a wire mesh so I think it can resist some damage.

I read about other approaches that make me marvel at mankind's genius. For instance, on the moon you could slowly spin a pool of liquid Mercury to obtain a radio telescope that is basically immune from microimpacts. Not sure how it would work once the mercury freezes solid due to lack of sunlight, but I think it's such a beautiful (but maybe impractical) idea :).

3 comments

You can do that on earth, too. See https://en.wikipedia.org/wiki/NASA_Orbital_Debris_Observator..., https://en.wikipedia.org/wiki/Large_Zenith_Telescope for (decommissioned) examples (both found via https://en.wikipedia.org/wiki/Liquid-mirror_telescope)

The idea apparently came from Isaac Newton.

> Not sure how it would work once the mercury freezes solid due to lack of sunlight, but I think it's such a beautiful (but maybe impractical) idea :).

Can't you heat it through induction heating? Vacuum is good isolation, so it won't lose heat too fast. Keeping whole pool above -30 °C probably won't require too much energy.

Maybe. I honestly don't know and just read about it quite a while ago and can't remember the details.
But mercury is a heavy metal. It must be prohibitively expensive to transfer the amount needed to the moon from earth.
Agreed, that's why I wrote maybe impractical. I just find it fascinating :)