Science If a brown dwarf orbited the Sun at the same distance as Jupiter, would life have evolved on Earth?
Science What would cause Earth’s orbit to become more circular instead of its present elliptical orbit, and has this ever happened before?
Science How can astronomers tell the difference between a group or cluster of stars and an actual galaxy?
Science Could the huge gamma-ray bubbles that extend above and below the center of the Milky Way be a boundary of matter and antimatter, whose collision emits gamma rays?
