| Astrophysics (Index) | About |
Transiting Exoplanet Survey Satellite (TESS) is a NASA MIDEX spacecraft surveying two million nearby stars for transiting planets. It has four wide-angle telescopes, storing three months of data, allowing it to prioritize transmission of promising data to ground stations. Its intended targets are stars brighter than +12 magnitude, including G-type stars and K-type stars, as well as nearby M dwarfs, small M-type stars. TESS was launched in April 2018 for a 2-year primary mission, after which extension was approved, beginning additional observations in July 2020. The satellite remains usable, useful, and active in 10/2026 with observations planned through at least 9/2027.
The TESS project began as an offshoot of the High Energy Transient Explorer (HETE) gamma-ray burst series, originally called HETE-S (for Hot Exoplanet Transit Explorer-Survey), aiming to adapted HETE technology, making use of the ongoing improvements in optical CCDs to perform an all-sky survey for exoplanets.
TIC stands for TESS input catalog. TOI stands for TESS object of interest, a term for a planet candidate, i.e., the location of observations that appear to reveal a transiting planet. TFOP (for TESS Follow-up Observation Program) is an effort to investigate TESS discoveries, e.g., to confirm whether a TOI is a planet. CTOI stands for community TOI, which, with the TIC number, is used to designate such objects that were identified and shared by independent researchers rather than those of the TESS program itself. As of June 2026, TESS has produced over 8000 candidates (TOIs) among its target stars, including at least 1700 apparently between Earth and Neptune in radius, and 897 confirmed to be planets through follow-up observation.
The terms TESS Duo and TESS-bis have been used the a concept of launching a second TESS satellite. TESS spots many transients (e.g., supernovae) as well as SSSBs, and an additional TESS, taking advantage of the existing design, could offer immediate confirmation of apparent transients as well as parallax regarding solar system objects.
|