TESS stands for Transiting Exoplanet Survey, and this telescope was developed with the main purpose of finding distant planets which can be habitable for humans. This telescope will be launched on Wednesday, April 18 from Space Launch Complex 40 (SLC-40) at Cape Canaveral Air Force Station, Florida (previous date April 16).
This telescope is a stepping stone for the future goals of NASA. It can only identify planets which have a chance to be habituated. Further findings like the details on the atmosphere of all the planets found with this telescope will be observed in the future missions of NASA. The light emitted from a host star can be seen passing through the layer of gasses of a planet. With the help of this light, one can observe and study the spectral signature or other chemical imbalances of the molecules in the atmosphere of the respective planet. The most visible spectral signature will be that of hydrogens.
After TESS is launched, it will start a survey of the whole sky starting from the Southern Hemisphere in the first year and then will move onto the survey of the Northern Hemisphere in the second year. Researchers are hoping to identify at least 50 planets which will be less than four times the diameter of the Earth of which a few of them might be in their star’s habitable zone. During its whole period of operation, the telescope will be pointed away from the sun. It will be pointed in the anti-solar direction for 27 days and will move on to the next anti-solar direction and will observe there for the next 27 days. By doing so, the telescope will oscillate in a 13.7-day orbit between 108,000 to 373,000 kilometers above the Earth’s surface.
TESS will only be able to grasp few details of the planets, and there are a variety of other factors which determine whether a planet can be habitable or not. This telescope will act as a finder scope for the next more advanced missions to come, like the NASA’s next telescope the James Webb Space Telescope, which is expected to be launched in the year 2020. The aim of Webb is to find further information about the planet’s atmosphere and characterize it and also to search for the existence of water in the rocky worlds which orbit their stars. If TESS can achieve its goal, we will be able to add few more planets to the list of TRAPPIST-1 and Proxima Centauri, which are nearby planet-hosting stars.