The Wide Field InfraRed Survey Telescope (WFIRST) is now called the Nancy Grace Roman Space Telescope. It is a NASA observatory designed to settle essential questions in the areas of dark energy, exoplanets, and infrared astrophysics. It’s primary mirror will be 2.4 meters in diameter (7.9 feet) and it will have two instruments, the Wide Field Instrument and the Coronagraph Instrument.