A footologist
Someone who studies evolution is called Evolutionary Biologist.
Someone who studies cryogenics is called a cryogenicist.
A historian studies history.
The name for someone who studies caves is a speleologist or a spelunker.
A psychologist is the proper name for someone who studies the mind.
Podiatrist
Yes, someone who studies bats is called a chiropterologist.
There is no special name for someone who studies Hebrew.
Someone who studies planetary systems is called a planetary scientist
A magnetometer is a device used to measure the intensity and direction of a magnetic field.
A gemologist studies gems.
a person who studies planets is a planetologist.