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 (July 2018-July 2019), the southern ecliptic hemisphere was observed. During Year 2 of the mission (July 2019-July 2020), the northern hemisphere was observed. During Year 3 of the mission (July 2020-July 2021), the southern ecliptic hemisphere is being re-observed. During Year 4+ (July 2021-September 2022), parts of the northern ecliptic hemisphere will be re-observed, and a 240° swath of the ecliptic will be observed for the first time. 

As of 10 May 2020, TESS has identified 1835 candidate exoplanets, of which 46 have been confirmed so far. 

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).