In an unprecedented discovery, astronomers have detected a rare exoplanet located at the very edge of the Milky Way galaxy, using a method grounded in Albert Einstein’s theory of general relativity.

Astronomers have found thousands of exoplanets around single stars, but few around binary stars—even though both types of stars are equally common. Physicists can now explain the dearth.

Using gravitational microlensing, scientists have discovered a rare, large planet at the edge of the Milky Way. The planet is only the third to be found on the outskirts of our galaxy's dense central ...