From UPSC perspective, the following things are important :
Prelims level : TOI 270
Mains level : Exoplanets and thier habitability
- It is the name of the dwarf star and the planetary system recently discovered by NASA’s Transiting Exoplanet Survey Satellite (TESS).
- TOI 270 is about 73 light years away from Earth, and is located in the constellation Pictor.
- Its members include the dwarf star, which is 40 per cent smaller than the Sun in size and mass, and the three planets or exoplanets (planets outside the solar system) that have been named TOI 270 b, TOI 270 c, and TOI 270 d.
- These three planets orbit the star every 3.4 days, 5.7 days, and 11.4 days respectively. In this system, TOI 270 b is the innermost planet.
Nature of the planets
- Researchers expect it to be a rocky world about 25 per cent bigger than Earth.
- It is not habitable since it is located too close to the star — about 13 times closer than our Solar System’s Mercury is from the Sun.
- On the other hand, TOI 270 c and TOI 270 d are Neptune-like planets because their compositions are dominated by gases rather than rock.
- Planet d, which is suspected to have a rocky core covered by a thick atmosphere, offers a surface unfavorably warm for the existence of liquid water, thereby rendering the planet potentially uninhabitable.
About Transiting Exoplanet Survey Satellite (TESS)
- TESS is NASA’s latest satellite to search for planets outside our solar system, known as exoplanets.
- The mission will spend the next two years monitoring the nearest and brightest stars for periodic dips in their light.
- TESS is expected to transmit its first series of science data back to Earth in August, and thereafter periodically every 13.5 days, once per orbit, as the spacecraft makes it closest approach to Earth.
- These events, called transits, suggest that a planet may be passing in front of its star.
- TESS is expected to find thousands of planets using this method, some of which could potentially support life.