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You wouldn't want to put up cell towers near the radio telescopes. Green Bank has a 10 mile zone where radio activity is restricted, and on the moon you could p

by lacker 5y ago

You wouldn't want to put up cell towers near the radio telescopes. Green Bank has a 10 mile zone where radio activity is restricted, and on the moon you could probably get much more space dedicated to telescopes for a long time. But even if one day there starts to be some radio interference due to activity on the moon, the lack of atmosphere will probably always cause there to be orders of magnitude less interference, and there are some wavelengths that simply can't be observed from the earth because of atmospheric interference.

garmaine 5y ago
> and there are some wavelengths that simply can't be observed from the earth because of atmospheric interference. Of particular relevance is the frequency associated with the transition from opaque plasma to neutral matter, which made interstellar space transparent. This coincides with the first stars, and is as close to the Big Bang as we can observe. Cosmologists are very interested in generating a detailed cosmic map at these frequencies, but they are unfortunately blocked by (1) the ionosphere of the Earth's atmosphere, and (2) subject to tons of radio interference. It's like right smack in the middle of the most commonly used frequency bands. Lunar far-side observatories are pretty much the best path towards making these measurements.
- rbanffy 5y ago
  How large would a lander need to be to still be able to make useful observations from a point on the far side? Or even the near side, as the noise would come from the Earth and a directional antenna can always look the other way. A 3m dish would fit on an LM-sized lander and that’s “relatively simple” tech.
  - garmaine 5y ago
    Pizza-box sized omnidirectional antennas was the plan, I think. A couple of them spread out over a large area like a crater floor. And yes, they were looking at robotic deployment.
    - rbanffy 5y ago
      I was looking more for the simplest-possible deployment. A dish on top of a single lander is probably easy, but now that I'm thinking of it, the arrangement only makes sense if we have a human settlement nearby to maintain and upgrade it - if not, just having a larger dish and never landing anywhere is a much better idea. With a number of landers, if they are all in line of sight of each other, optical interferometry becomes a lot easier.
      - garmaine 5y ago
        Look at the DARE mission proposal.

by lacker 5y ago

garmaine 5y ago

> and there are some wavelengths that simply can't be observed from the earth because of atmospheric interference. Of particular relevance is the frequency associated with the transition from opaque plasma to neutral matter, which made interstellar space transparent. This coincides with the first stars, and is as close to the Big Bang as we can observe. Cosmologists are very interested in generating a detailed cosmic map at these frequencies, but they are unfortunately blocked by (1) the ionosphere of the Earth's atmosphere, and (2) subject to tons of radio interference. It's like right smack in the middle of the most commonly used frequency bands. Lunar far-side observatories are pretty much the best path towards making these measurements.

rbanffy 5y ago
How large would a lander need to be to still be able to make useful observations from a point on the far side? Or even the near side, as the noise would come from the Earth and a directional antenna can always look the other way. A 3m dish would fit on an LM-sized lander and that’s “relatively simple” tech.
- garmaine 5y ago
  Pizza-box sized omnidirectional antennas was the plan, I think. A couple of them spread out over a large area like a crater floor. And yes, they were looking at robotic deployment.
  - rbanffy 5y ago
    I was looking more for the simplest-possible deployment. A dish on top of a single lander is probably easy, but now that I'm thinking of it, the arrangement only makes sense if we have a human settlement nearby to maintain and upgrade it - if not, just having a larger dish and never landing anywhere is a much better idea. With a number of landers, if they are all in line of sight of each other, optical interferometry becomes a lot easier.
    - garmaine 5y ago
      Look at the DARE mission proposal.