Arecibo was also a massively powerful radar transmitter, used to map other bodies in our solar system and arguably more importantly to get precise position and

Arecibo was also a massively powerful radar transmitter, used to map other bodies in our solar system and arguably more importantly to get precise position and trajectory information for the various objects floating around out there. Losing it is a massive hit to our ability to accurately track potential asteroid threats. Now we're down to just Goldstone, which is both much less powerful and has a much smaller dish.