TESS Space Telescope

TESS is a space telescope developed to detect exoplanets orbiting stars other than Solar System. Its mission is to identify regular dips in brightness caused by planets' passing in front of particularly nearby and bright stars, thereby identifying new planet candidates.

^{An image of the TESS Space Telescope (}Anadolu Agency⁾

The primary goal of TESS is to survey a large portion of the sky to detect numerous exoplanet candidates. Unlike previous space telescopes which focused on narrow fields, TESS employs an observation strategy that covers nearly the entire sky. This approach aims to identify planets in stellar systems close to the Sun that are suitable for detailed follow-up studies. The findings provide fundamental information on the sizes orbital periods and relationships of these planets with their host stars.

TESS divides the sky into specific sectors and observes each region continuously for extended periods. This systematic survey method allows the same stars to be monitored for weeks, enabling reliable detection of brightness variations caused by regular planetary transits. The mission plan covers both the southern and northern celestial hemispheres over its operational lifetime.

TESS uses the photometric transit method. When a planet passes in front of its host star it causes a small but measurable decrease in the star’s light. TESS’s high-sensitivity cameras record these changes. The collected data are analyzed using computer-assisted methods to identify planet candidates. These candidates are then directed to other to telescopes for confirmation and detailed characterization.

TESS space telescope is equipped with four cameras with wide fields of view arranged to observe large portions of the sky simultaneously. The satellite orbits Earth in an elliptical path that minimizes observational interruptions caused by gravitational influences from Earth and the Moon, enabling long-term stable measurements. TESS has the photometric precision required to measure light from bright stars with high accuracy.

Data collected by TESS are used not only for exoplanet detection but also in the field of stellar physics. Phenomena such as stellar oscillations variable stars and binary star systems can be studied in detail using TESS data. In this regard the mission serves as a multi-purpose observational platform contributing to various subfields of astrophysics.