Learn about the life and scientific contributions of Johannes Kepler, the 17th-century astronomer known for his laws of ...

Although the occurrence climaxed on Jan. 21 with a conjunction—close alignment—of Saturn and Mercury, the planetary parade ...

Among the roughly 10 billion white dwarf stars in the Milky Way galaxy, a greater number than previously expected could ...

Raised in the Lutheran church, Tycho was led to believe that the earth was the center of the universe, but his carefully ...