This would be called a meteorologist. Typically, meteorologists are associated with reporting weather - but weather is determined by these planetary atmospheres that meteorologists spend their time studying.
Geologist - specifically a 'Vulcanologist'
The category of oceanographer called a physical oceanographer
biogeochemical
Leonardo da Vinci was known for Painting the Mona Lisa& The Last Supper and for being a scientist and an inventor.He invented the parachute. He also studied the symmetry of human anatomy.
Honestly, you're in luck. In a few weeks on December 21, 2020, Jupiter and Saturn will align... a real Christmas star. (By the way people think the Christmas Star is Jupiter, Saturn, and Venus.) These things are rare... the last Jupiter-Saturn alignment was in 1226... Now for all the planets, hmm. I'd say it won't happen in the next 10,000 years. Even Wikipedia has ecliptic events for 500,000 AD. Unlike what many think, it's not going to be the end.
The name for this type of scientist is a teuthologist
A geological scientist studies rock and stones.
a type of scientist who studies about metal is called metallururgist
A scientist who studies animal life is a zoologist. There is no particular name for a scientist that specialises in platypuses.
The type of scientist that studies the environment is an enviromentologist.
what scientist studies hydrogen and oxygen
chromotologists
Aeronomist
A botanist.
An Entomologist
taxonomistBotanist
A zoologist.