TESS space telescope can find an estimated 10,000 new exoplanets

According to calculations and estimates by the scientists behind the recently-commissioned Transiting Exoplanet Survey Satellite, this space telescope can identify 10,000 exoplanets during its primary two-year mission.

In a publication, the astronomers report that of the 10,000 exoplanets, about 3,500 planets are about the same size or smaller than Neptune. Finding exoplanets of this size is TESS’s primary goal; these discoveries could help scientists better understand how small rocky planets are formed. The scientists say that with an extension of the two-year mission, an additional 2,000 planets could be discovered for each additional year.

The new estimate of 10,000 exoplanets is based in part on data from Gaia, an ESA spacecraft that has accurately mapped the position and distances of 1.5 billion stars in the Milky Way. Gaia’s data is useful for TESS because that data, combined with the perceived brightness, provides information about the size of the objects. Because the exact distance to the many stars is known, the instruments of TESS can also be better adjusted. This could help find perhaps 50 relatively small, Earth-like exoplanets.

TESS has recently started the search for exoplanets and the first data is expected this week. The satellite has four wide-angle cameras and has to observe a total of 85 percent of the visible space. That is considerably more than the Kepler satellite, the predecessor of TESS. The discovery of the exoplanets is done via the transit method, which looks for a small dip in the brightness of stars. If so, it could indicate a passing planet in front of the star.