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The near and far side of the moon spent the same amount of time in darkness, so there's no advantage gained by putting it on the far side. Edit: I just realiz

The near and far side of the moon spent the same amount of time in darkness, so there's no advantage gained by putting it on the far side. Edit: I just realized this idea comes from radio telescopes. Those would actually benefit from sitting on the far side of the moon, because that way they'd be shielded from the radio emissions of human civilization. That concept doesn't transfer to visible light or IR telescopes though.

CamperBob2 5y ago
The moon is tidally-locked, so the near side always faces Earth. It'd be a good place for a spy satellite, maybe, but less desirable for any kind of sensitive astronomical instrument. The Earth might as well be as big as the Sun from the perspective of the IR instrumentation on JWT. They'd prefer to keep it entirely out of their field of view, which is why it's being positioned at L2. Placing the telescope on the far side of the moon would have the same effect at least part of the time, and we'd potentially be able to carry out maintenance and upgrades in the future.