Transiting Exoplanet Survey Satellite – TESS
If Kepler Telescope was a revolutionary, TESS will take the next step in evolution of planet hunting when it is launched later today.
TESS or transiting exoplanet survey satellite, name scarcely does it justice when describing what this amazing piece of equipment will do for science, in particular exoplanet detection and science.
As of late 2017, we have discovered 3717 confirmed Exoplanets in around 2800 solar system, Kepler Telescope is responsible for discovery of 2512 of these Exoplanets or majority (67%). However majority of these planets are so far away that determining, the size, planetary composition or if the planet is in a habitable zone is at best educated guess.
Kepler also looked at really small, narrow fixed field of view in the sky, giving us limited number of stars, estimated @150 000, and limited number of earth-like planets we could possibly detected.
To say Kepler wasn’t a success, would be understatement, for the telescope discovered so many earth-sized planets, it surprised many astronomers who assumed Earth-sized planets are rare or uncommon.
TESS Telescope, has similar mission, however the objectives are somewhat different. The telescope will survey 85% of our skies, looking at nearest 200 000 stars using transit method, all within 200 light-years of Earth.
It is expected within 100 light-years or around 32 Parsecs, TESS will discover anywhere between 3800 and 8000 earth-sized planets, if we consider there are at least 37000 stars in this volume of space. TESS is expected to discover at least 20 000, if not 200 000 planets in short 2-3 years the telescope will survey the skies.
The TESS project will use an array of wide-field cameras to perform an all-sky survey. With TESS, it will be possible to study the mass, size, density and orbit of earth sized rocky planets, including a sample of earth sized worlds in the habitable zones of their host stars. TESS will provide prime targets for further characterization by the James Webb Space Telescope, as well as other large ground-based and space-based telescopes.
Previous sky surveys with ground-based telescopes have mainly detected Jupiter sized gas giant exoplanets. In contrast, TESS will examine a large number of small planets around the very brightest stars in the sky. TESS will record the nearest and brightest main sequence stars hosting transiting exoplanets, which are the most favorable targets for detailed investigations.
TESS mission parameter is designed to carry out all-sky transiting exoplanet survey, for that task it is equipped with four wide-angle telescopes and associated charge-coupled device, each camera features a low-noise, low-power 16.8 megapixel CCD detector, Each has a 24° × 24° field of view, Science data will be transmitted to Earth every two weeks.
TESS's two-year all-sky survey will focus on nearby G, K and M type stars. Approximately 200,000 stars will be studied, including the 1,000 closest red dwarfs across the whole sky,
The survey is broken up into 26 observation sectors, each sector being 24° × 96°, with an overlap of sectors at the ecliptic poles to allow for additional sensitivity toward smaller and longer-period exoplanets in that region of the celestial sphere.
The spacecraft will spend two 13.7 day orbits observing each sector, mapping the southern hemisphere of sky in its first year of operation and the northern hemisphere in its second year. Each of TESS's cameras will take one-minute exposures focused on specifically targeted stars as part of its transit search, and 30-minute full-frame exposures to search for other transient events.
TESS promises some hard to imagine science, it’ll take exo-planet science to whole new level, and the likelihood of discovery of Earth sized and earth like planet in an habitable zone are very promising. Just imagine discovering earth like planet, similar size, in habitable zone with all indications it might be Earth 2.0, the profound discovery would change how we view universe around.
However, only with completion of EELT or European Extremely large Telescope in 2024, would we get more accurate picture of any earth-Like planet discovered by TESS. TESS Will be launched by Falcon 9 full thrust rocket, SpaceX has loads riding on this one and who knows, if we do discover Earth 2.0 Elon Musk might start looking in to designing interstellar spaceship.
