The Transiting Exoplanet Survey Satellite (TESS) is a space telescope for NASA's Explorers program, designed to search for exoplanets using the transit method in an area 400 times larger than that covered by the Kepler mission. It was launched in April 2018, and the first light image was taken in August 2018.


The TESS satellite uses an array of wide-field cameras, making it possible to study the mass, size, density and orbit of a large cohort of small planets, including a sample of rocky planets in the habitable zones of their host stars.


During Year 1 of the mission (Jul 2018-Jul 2019), the southern ecliptic hemisphere was observed. During Year 2 of the mission (Jul 2019-Jul 2020), the northern hemisphere was observed. During Year 3 of the mission (Jul 2020-Jul 2021), the southern ecliptic hemisphere was revisited but with increased cadence options. During Year 4 (Jul 2021-Sep 2022), an optimized mix of northern and southern hemispheres were observed. During Year 5 (Sep 2022-Sep 2023) an optimized mix again was observed, similar to Year 6 (Oct 2023-Sep 2024), optimizing sector selection for better exoplanet characterization. TESS is currently (Mar 2025) in Orbit 186, observing Sector 89. 



Peranso uses data collected with the TESS mission, obtained from the MAST data archive at the Space Telescope Science Institute (STScI). Funding for the TESS mission is provided by the NASA Explorer Program. STScI is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5–26555. Peranso furthermore makes use of TESSCut, for creating cutouts of TESS images (see Brasseur et al. 2019).