The Nancy Grace Roman Space Telescope (shortened as Roman or the Roman Space Telescope, and formerly the Wide-Field Infrared Survey Telescope or WFIRST) is a NASA infrared space telescope currently in development and scheduled to launch by May 2027. Roman was recommended in 2010 by the United States National Research Council Decadal Survey committee as the top priority for the next decade of astronomy. On 17 February 2016, WFIRST was approved for development and launch. The Roman Space Telescope is based on an existing wide field of view primary mirror and will carry two scientific instruments. The Wide-Field Instrument (WFI) is a 300.8-megapixel multi-band visible and near-infrared camera, providing a sharpness of images comparable to that achieved by the Hubble Space Telescope over a 0.28 square degree field of view, 100 times larger than imaging cameras on the Hubble. The Coronagraphic Instrument (CGI) is a high-contrast, small field of view camera and spectrometer covering visible and near-infrared wavelengths using novel starlight-suppression technology. Stated objectives include a search for extra-solar planets using gravitational microlensing, along with probing the chronology of the universe and growth of cosmic structure, with the end goal of measuring the effects of dark energy, the consistency of general relativity, and the curvature of spacetime. On 20 May 2020, NASA Administrator Jim Bridenstine announced that the mission would be named the Nancy Grace Roman Space Telescope in recognition of the former NASA Chief of Astronomy's role in the field of astronomy. On 29 September 2021, NASA announced that Roman had passed its Critical Design Review (CDR), and that with predicted impacts from COVID-19 disruptions, the launch date would be no later than May 2027. As of July 2022, Roman is scheduled to be launched on a Falcon Heavy launch vehicle under a contract specifying readiness by October 2026 in support of a NASA launch commitment of May 2027. Development of mission The original design of Roman, called WFIRST Design Reference Mission 1, was studied in 2011–2012, featuring a diameter unobstructed three-mirror anastigmat telescope. It contained a single instrument, a visible to near-infrared imager/slitless prism spectrometer. In 2012, another possibility emerged: NASA could use a second-hand National Reconnaissance Office (NRO) telescope made by Harris Corporation to accomplish a mission like the one planned for Roman. NRO offered to donate two telescopes, the same size as the Hubble Space Telescope but with a shorter focal length and hence a wider