TESS will monitor more than 200,000 stars for temporary drops in brightness caused by planetary transits. This first-ever spaceborne all-sky transit survey will identify planets of all sizes.
Data release products include: Raw full frame images, calibrated full frame images, target pixels, light curves, flat fields, pixel response function, and lists of TESS Objects of Interest (TOIs).
Looking up at a dark night sky we can see up to thousands of stars. Every star is a sun and if our sun has planets it makes sense that the other stars have planets also, and they do. We now think that every star has a planetary system, meaning our Milky Way Galaxy is teeming with exoplanets. Astronomers are turning their attention to the nearest stars, those that are bright enough with enough photons so that we may further study the planets. The nearest stars are spread all around the sky, motivating an all-sky survey.
TESS is an MIT-led NASA mission, an all-sky survey for transiting exoplanets. Transiting planets are those that go in front of the star as seen from the telescope and, to date, is the most successful discovery technique for finding small exoplanets.
TESS has four identical cameras.
- Each has a 24×24 degree field of view
- They are aligned to cover 90×24 degree strips of the sky called ‘segments’
- The camera CCD detectors are 16 Megapixel with 20” pixels
- The detectors are red sensitive
TESS aims for 50 ppm photometric precision on stars with TESS magnitude 9-15, although brighter stars can also be monitored.
The TESS mission will downlink about 200,000 two-minute cadence postage stamps, as well as full frame images binned on board to 30 minute cadence.
The team has prepared the TESS Input Catalog of over 1 billion objects, with a special subset Candidate Target List of 200,000 objects for the two-minute cadence observations.
TESS will tile the sky with 30 segments, observing the southern hemisphere in the first year of mission operation and the northern hemisphere in the second year. TESS has a unique, 13 day, highly elliptical cislunar orbit about Earth. With a 27 day observing period per segment,
The satellite is most sensitive to exoplanets with a periods of less than 13 days (so that two transits are used for discovery). The period range can correspond to the habitable zone of small red dwarf stars, the region around the star where a planet with a thin atmosphere is heated by the star to have a surface temperature not too hot, not too cold but just right for life.
The segment overlap at the ecliptic poles makes an observing period of just over 100 days, enabling longer period planets to be discovered.
TESS anticipates the discovery of thousands of exoplanets of all sizes around a variety of star types. It has committed to delivering 50 planets of size less than 4 Earth radii with measured masses to the community. An international effort under the TESS Followup Program are committed to observations to distill the TESS planet candidates down to the list of 50 with measured masses, using the best ground-based telescopes in the world.
TESS is scheduled to launch no earlier than March 20, 2017 on a SpaceX Falcon 9 rocket out of Cape Canaveral.