Scientists from Physical Research Laboratory (PRL), Ahmedabad have discovered for first time distant planet revolving around Sun-like star. Both the planet and the star have been named EPIC. With this discovery India joins handful of countries which have discovered planets around stars.
The planet has been named as EPIC 211945201b (or K2-236b) and host star has been named EPIC 211945201 (or K2-236). The EPIC planet is six times bigger than Earth and revolves around host about 600 light years away. EPIC was found circling very close to its host star, going around it once in about 19.5 days.
EPIC planet is smaller in size compared to Saturn and but is bigger than Neptune. Its mass is about 27 times Earth’s and six times that of Earth at radius. Its 60% mass may be made up of heavy elements like ice, silicates and iron. The planet is unlikely to be inhabitable because of its high surface temperature of around 600°C.
The discovery was made using PRL-designed PARAS (PRL Advance Radial-velocity Abu-sky Search) spectrograph to measure and confirm the mass of the new planet. PARAS is first of its kind spectrograph in the country which can measure the mass of planet going around star. It is integrated with 1.2-metre telescope located at PRL’s Gurushikhar Observatory in Mount Abu, Rajasthan. Very few such spectrographs exist around the world (mostly in US and in Europe) that can do such precise measurements.
The discovery of EPIC planetary system adds to sparse catalogue of 22 other confirmed exoplanet systems that have mass and radius in range between Saturn and Neptune. It will help in understanding formation mechanism of such super-Neptune or sub-Saturn kind of planets that are too close to host star. This planet is very unlike those in our own Solar System, by studying them will tell us more about how planetary systems are formed.
Physical Research Laboratory (PRL)
It is national research institute for space and allied sciences, supported mainly by Department of Space (DST) of Government of India. It conducts research programmes in astronomy and astrophysics, atmospheric sciences and aeronomy, solar system, Earth sciences and theoretical physic. It was founded in November 1947 by Dr. Vikram Sarabhai. It is located in Ahmedabad, Gujarat.