Answer:

astronomers

Answer	Crossword Clue
ASTRONOMERS	Halley and Herschel.
ASTRONOMERS	Shapely, Hale, etc.
ASTRONOMERS	Some Pythagoreans

ASTRONOMERS	Moon starers! (Anagram)

Crossword

a puzzle consisting of a grid of squares and blanks into which words crossing vertically and horizontally are written according to clues.