TESS (MIDEX 7, Explorer 95)

Launch data: Designation  43435 / 18038A Launch date  18 Apr 2018 - 22:51 UT Launch site  CC, SLC-40 Launch vehicle  Falcon-9 v1.2 Mission  Astronomy observatory Earth orbit: Perigee / Apogee  249 x 268294 km Eccentricity   Inclination  29.6° Period   min

Spacecraft data:

Description:

• The discovery of thousands of exoplanets in recent years is one of the most exciting developments in space exploration, and the future promises the detection of thousands more. Many of those have come from the Kepler Space Telescope, including Earth-sized planets in the habitable zones of their stars, but that mission will soon be coming to an end as the telescope runs out of fuel. It will be replaced by the next generation of planet-hunting space telescopes.
• The Transiting Exoplanet Survey Satellite (TESS) is the next step in the search for planets outside of our solar system, including those that could support life. The mission will find exoplanets that periodically block part of the light from their host stars, events called transits. TESS will survey 200,000 of the brightest stars near the sun to search for transiting exoplanets.
• TESS scientists expect the mission will catalog thousands of planet candidates and vastly increase the current number of known exoplanets. Of these, approximately 300 are expected to be Earth-sized and super-Earth-sized exoplanets, which are worlds no larger than twice the size of Earth. TESS will find the most promising exoplanets orbiting our nearest and brightest stars, giving future researchers a rich set of new targets for more comprehensive follow-up studies.
• Why is TESS so important? Kepler focused on a small patch of the sky, detecting exoplanets very far away. TESS, however, will conduct a sky-wide survey, looking at the nearest and brightest stars; TESS stars will be 30-100 times brighter than those surveyed by Kepler, and can cover an area 400 times larger than what Kepler covered. In doing so, TESS aims to discover not just exoplanets, but specifically seeks to identify habitable, Earth-like worlds
• Over at least two years, TESS will survey more than 200,000 stars, and will be able to find many new exoplanets orbiting these stars, including Earth-sized and super-Earth-sized (larger than Earth but smaller than Neptune), which are now known to be the most common in our galaxy. Later upcoming space telescopes, such as the James Webb Space Telescope (JWST), will be able to then study these planets further and analyze their atmospheres for possible signs of life.
• The main objective of the mission is to find smaller rocky planets, like Earth, orbiting closer stars in the solar neighborhood. It is anticipated that TESS will discover more than 3,000 planetary candidates and about 500 Earth-sized or super-Earth-sized worlds.

TESS pre-launch. Photo Credit: NASA

TESS in the clean room at Kennedy Space Center. Photo Credit: Jeff Seibert/AmericaSpace

Mission details:

• The Transiting Exoplanet Survey Satellite (TESS), an astronomical observatory in NASA′s Explorer program, was launched on Apr 18, 2018 by Falcon 9. TESS will survey the sky to find exoplanets transiting bright stars and nearby stars. The Falcon 9 entered an initial 250 x 250 km orbit and then restarted to place TESS in a 280 x 272166 km x 29.6 deg highly elliptical orbit. The second stage then made a third burn for disposal, and entered a hyperbolic orbit leading to a 0.83 x 1.00 AU x 0.3 deg solar orbit.
• TESS will make a lunar flyby on May 27, 2018 and reach a half-month-period operational orbit on Jun 12. It will spend two years staring at sectors of the sky for a month at a time until it has searched the entire sky for transiting exoplanets. While the search is limited by the brightness of the host stars and the large (21 arcsecond) camera pixels, and by the probability that a planet and its star are oriented in such a way as to cause a transit seen from Earth, TESS should discover a large number of exoplanets that are, unlike the Kepler planets, close enough for detailed spectroscopic followup by other observatories.
• The TESS exoplanet hunter reached its first perigee at 0542 UTC Apr 25, 2018 and made a successful burn to raise apogee to lunar distance. Apogee 2 was at 1903 UTC Apr 29, at 353440 km. TESS made an 8119 km lunar flyby at 0632 UTC May 17, leaving it in a 100000 x 449000 km x 36.4 deg orbit around Earth. Meanwhile, the TESS cameras were tested successfully; regular observations should begin in June.
• On May 30, 2018 at 0130 UTC TESS made its final orbit insertion burn, changing the orbit from 99036 x 435600 km x 36.6 deg to 99037 x 366905 km x 36.6 deg, a P/2 lunar resonant orbit. Instrument commissioning is underway and TESS should begin its search for extrasolar planets soon.
• The TESS observatory has completed commissioning and begun its first set of exoplanet search observations (July 2018).

External links:

• NASA: Satellite Information
• Satellite tracking (n2ya.com): Real time satellite tracking

Astrophilately covers:

Launch cancel Kennedy Space Center.

Launch cancel Goddard Space Flight Center. Credit both: #402