The Roman Space Telescope is a NASA observatory designed to settle essential questions in the areas of dark energy, exoplanets, and infrared astrophysics. The telescope has a primary mirror that is 2.4 meters in diameter (7.9 feet), and is the same size as the Hubble Space Telescope's primary mirror. The Roman Space Telescope will have two instruments, the Wide Field Instrument, and the Coronagraph Instrument technology demonstration.