[PeaceBeWithYou]

It occurs to me that if the Sun is the cause, warming should be found thruout the solar system(all planets/moons). I don't know if anyone has looked specifically at all of the planets and moons for warming. So far, AFAIK it seems to have been found only by accident.

[KeyWest]

Found by those who were studying the specific planet/moon. I believe both Neptune and Mars were by grad students. Most astronomers are interested in things far beyond out solar system. That is where the grant money is.