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by emirp 2393 days ago
Why would you put antennas behind the moon?

I read the article: these antennas are radio telescopes (or perhaps just do the same job). So they're using the moon to block interfering radio signals from Earth.

2 comments

They're listening to a doppler shifted version of the hydrogen alpha spectral line (~450 THz doppler shifted down to ~30 MHz) down to about the VHF television band (hence the almost "rabbit ears" style antennas). Being on the other side of the Moon shields them from powerful terrestrial transmitters. The massive doppler shift means they're listening (observing) to bubbling atoms of hydrogen closer in time to the Big Bang than what was observed by COBE or WMAP.

https://lambda.gsfc.nasa.gov/product/cobe https://map.gsfc.nasa.gov

> We have the opportunity to perform our observations during the fourteen-day-long night behind the moon, which is much longer than was originally the idea.

And from the sun.

> The moon night is ours, now.

That probably sounds less creepy in Dutch.

"De maan is nu van ons" ;-)
This reminds me of another instance of Dutch hubris:

https://beeldbank.rws.nl/MediaObject/Details/Monument__Hier_...