Answer:

ASTRONOMER

Answer	Crossword Clue
ASTRONOMER	SIR CHRISTOPHER WREN
ASTRONOMER	A student hoping to become an ... took a short-answer test...
ASTRONOMER	Celsius, for one

ASTRONOMER	Hubble, for one
ASTRONOMER	Galileo, for one
ASTRONOMER	Copernicus, notably
ASTRONOMER	Apt anagram of MOON STARER
ASTRONOMER	Sir James H. Jeans.
ASTRONOMER	Shapley, for example.
ASTRONOMER	Palomar scientist.
ASTRONOMER	Tycho Brahe, for one

ASTRONOMER	What a mixed-up "moon-starer" really is
ASTRONOMER	Halley, e.g.
ASTRONOMER	His business is looking up
ASTRONOMER	Galileo was one
ASTRONOMER	One who knows what's up?
ASTRONOMER	Satellite tracker