L 98-59b: NASAâ€™s TESS discovers new planetDate: 28 June 2019 Tags: Space
NASA’s Transiting Exoplanet Survey Satellite (TESS) has discovered new planet named L 98-59b. Its size is between of Mars and Earth i.e. around 80% Earth’s size. It is far tiniest finds of TESS. It orbits a bright, cool, nearby star named L 98-59. The host star is about one-third the mass of Sun and lies about 35 light-years away.
Apart from L 98-59b, two other planets L 98-59c and L 98-59d also orbit L 98-59. L 98-59c and L 98-59d, are around 1.4 and 1.6 times Earth’s size.
Signifcance of Discovery: It is great engineering and scientific accomplishment for TESS. Such small planets are difficult to detect as they have short orbits around bright stars. This planetary system has the potential for fascinating future studies. Further study with other telescopes of this planetary system and planets in needed to determine whether they have atmospheres and, if so, which gases are present.
About Transiting Exoplanet Survey Satellite (TESS)
It is space telescope launched as part of NASA's Explorers program. It was launched in April 2018 for two-year mission atop Space X’s Falcon 9 rocket.
It is aimed at searching for exoplanets using transit method in an area 400 times larger than that covered by its predecessor Kepler mission.
Its primary mission objective is to survey brightest stars near Earth for transiting exoplanets. It uses array of wide-field cameras to perform survey of 85% of the sky.
It finds large number of small planets around nearest stars in sky as compared to previous sky surveys with ground-based telescopes which have mainly detected giant exoplanets
Significance of TESS: With TESS, it is possible to study mass, size, density and orbit of large cohort of small planets, including sample of rocky planets in habitable zones (or Goldilocks zone) of their host stars. It also provides prime targets for further characterization by James Webb Space Telescope, as well as to other large ground-based and space-based telescopes of the future.