Roman Space Telescope

The Roman Space Telescope (RST, or Nancy Grace Roman Space Telescope, earlier known as WFIRST for Wide Field Infrared Survey Telescope) is a planned near infrared NASA space observatory for dark energy/cosmology and extra-solar planet research, including a coronagraph for exoplanet direct imaging. Plans also include significant surveying for gravitational microlensing transients, e.g., to discover difficult to see astronomical objects such as planets including field planets, brown dwarfs, low mass stars, and compact objects. The telescope is a surplus National Reconnaissance Office telescope with the same mirror diameter as HST (2.4 meters) but a shorter focal length, thus a larger field of view. Current plans are to launch in late August 2026, for an orbit at L2 to carry out a 5-year primary mission with potential for extension. Instruments:

• CGI aka WFIRST CGI - Coronagraph Instrument.
• WFI aka WFIRST WFI - Wide Field Instrument (to include a slitless spectrograph).

Current survey plans include

• HLWAS (High-Latitude Wide-Area Survey: galaxy images to observe weak lens).
• HLTDS (High Latitude Time Domain Survey: supernova search).
• GBTDS (Galactic Bulge Time Domain Survey: microlensing search).

The original WFIRST proposal (2011-2012) included a new 1.3-meter telescope. While the current plan was under consideration but not yet adopted, it was called WFIRST-AFTA (Astrophysics Focused Telescope Assets). WFIRST is essentially a rename of the JDEM (Joint Dark Energy Mission) proposal (of circa 2005-2010), a mission plan superseding various dark energy research proposals, including SNAP (Supernova Acceleration Probe), Destiny (Dark Energy Space Telescope), and ADEPT (Advanced Dark Energy Physics Telescope).