Direct Imaging and Beyond

Direct imaging captures actual photographs of exoplanets by blocking the star's glare with a device called a coronagraph. It works best for large, young, hot planets far from their star. The first directly imaged system was HR 8799, showing four giant planets 129 light-years away.

Two other methods fill the gaps. Gravitational microlensing detects a planet when its star passes in front of a more distant star, bending and magnifying the background light. Astrometry tracks a star's tiny side-to-side shift in position. Combining methods gives the most complete census of planetary systems.