Milky Way Our solar system is in an outer spiral arm of the Milky Way, but do we know where our galaxy is within the universe?
Deep-Sky Objects Messier’s 102nd entry is known as the lost Messier object. Has there been any agreement on what this M object might be?
Stars Sirius, our brightest star, is orbited by a white dwarf — a dead star’s core. Where is the planetary nebula that would have formed when it shed its skin?
Exoplanets, Planets At tens, hundreds, or thousands of light-years from a star, how do you distinguish between exoplanets, sunspots, and dwarf binary companions?
Exoplanets, Planets, Solar System On the martian surface, would the moons Deimos and Phobos be visible to the unaided eye?
