NASA's Nancy Grace Roman Space Telescope, a future observatory for dark energy and exoplanets.The Nancy Grace Roman Space Telescope, formerly known as WFIRST, is a NASA observatory scheduled for launch in the late 2020s. It is designed to address fundamental questions in cosmology, particularly the nature of dark energy, and to discover and characterize exoplanets. With a wide field of view and infrared capabilities, Roman will survey large areas of the sky, complementing the James Webb Space Telescope's deep, narrow views.
The telescope is named after Nancy Grace Roman, NASA's first chief of astronomy, who was instrumental in the development of the Hubble Space Telescope. The mission was first proposed in the 2000s as the Joint Dark Energy Mission and later renamed WFIRST before being renamed again in 2020.
Roman's primary instrument is a 2.4-meter mirror (the same size as Hubble's) equipped with a wide-field infrared camera. It will measure the positions and shapes of hundreds of millions of galaxies to map the distribution of dark matter and trace the expansion history of the universe. For exoplanets, it will use microlensing to detect planets by the gravitational bending of light from background stars, and it will also directly image giant planets using a coronagraph to block starlight.
Roman will provide data for dark energy studies, exoplanet demographics, and infrared surveys of the Milky Way and nearby galaxies, serving the broader astronomical community.
Roman's field of view is 100 times larger than Hubble's infrared camera, allowing it to map the sky much faster.

















