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Comment by kristopolous | Hacker News Reader

There's more. The triangulations would provide some really great confirmation and precision on a number of things.

The unanswered question is if this is blocked out from earth communication, what are you doing for earth communication? Moon satellites? Optical relays? Would it go to the Mars satellites? These things get booked so far ahead of time, you can probably pretty easily schedule the dark times when it couldn't talk to Mars especially if you send it up with modern storage tech.

I guess there's also Venus satellites coming around soon as well.

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Why not put relay satellites that orbit the moon?

Actually I think this is already being planned anyway, unrelated to a telescope.

The moon is insanely hard to orbit because it's gravity is very lumpy

https://www.nasa.gov/feature/does-anything-orbit-the-moon-we...

For close orbits, and far orbits are difficult because Earth’s gravity interferes—-to save others a click.

what about some sort of Lagrange point orbit rather than orbiting the moon itself?

Lagrange point orbits are unstable as well.

It all can be done but takes propellant.

the moon is after all just a bunch of collision dust. It's a weird thing. https://www.youtube.com/watch?v=kRlhlCWplqk

What's really cool about CAPSTONE is that it's the first spacecraft to test the entrance and sustainability of a very unique near rectilinear halo orbit, also known as NRHO. This NRHO orbit is at a precise balance point between the gravities of the Earth and the Moon, which offers a long, stable orbit so that Gateway and future spacecraft don't have to carry so much fuel to stay in orbit around the Moon.

So that implies that in the Apollo missions, the command module had to burn fuel to stay in orbit around the moon? And I guess if anything had delayed the landing module from its scheduled return, the command module might have run out of fuel and been forced to abandon the astronauts on the moon?

The command module orbited fewer times than a satellite would have to.

It would probably be cheaper to put several relay satellites in extra-lunar orbits around Earth. Earth's gravity has a tendency to complicate lunar orbits.

Or put a relay in a halo orbit at earth-moon L2. Or at the earth-moon L4 and L5 orbits, which would cover a good portion of the moon's far side.

Satellites are also one of the biggest sources of radio frequency interference. (I did my PhD in radio astronomy and currently work on multiwavelength astronomy.)

There is no shortage of lunar communication satellite projects. ESA has Moonlight/Pathfinder, NASA has LCRNS/LunaNet, CNCA has its own projects (e.g. Queqiao), and there are even private efforts.

I'd just run a bundle of optical fibre cables over the horizon to the nearside and transmit to earth from there?

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