Chilean astronomers discover two new giant planets

The first of the planets (K2-237 b) orbits around its star every two days, while the second (K2-238 b) does so for three days. The two planets have a slightly higher mass than Jupiter.

Two Chilean and one Scottish scientist discovered two new exoplanets of the "hot Jupiter" type, huge gas balls similar to the colossus of the Solar System, orbiting two different stars, K2-237 and K2-238, in the constellations of Ophiuchus and Aquarius.

The first of the planets (K2-237 b) orbits around its star every two days, while the second (K2-238 b) does so for three days. The two planets have a slightly higher mass than Jupiter.

It is estimated that both planets are composed mainly of Hydrogen and Helium. In the specific case of K2-237 b, it is striking because it is an "inflated planet", that is, its size is much greater than what the theoretical models indicate, is a very interesting planet for atmospheric studies, says the PhD in Astronomy from the University of Chile and first author of the paper, Maritza Soto.

To detect these planets, different space instruments were used and installed in Chile, among which are: the Kepler 2 space probe, the data of the Coralie instruments (in the 1.2 meter Swiss telescope), FEROS (in the 2.2 meters) and HARPS (in the 3.6 meter telescope), all of them located in the La Silla Observatory of ESO.

Giant planets like Jupiter should have a similar mass, as the models indicate, but a group of them have a much larger mass, which is called inflation. The theory states that inflation is caused by the heat that falls on the planet from the star, which penetrates deep inside and inflates it like a balloon, says James Jenkins, an academic at the Department of Astronomy FCFM U of Chile and researcher of the CATA Center for Excellence in Astrophysics.

Soto, who led the research, explains that the main contribution of the research is that it "provides evidence for the study of planetary inflation. Inflation is a phenomenon that is seen in many planets "hot Jupiter", but that we still manage to understand completely ".

The data received from K2-237 b follows the theory that inflation occurs because of a large amount of radiation received by these planets. The next step in this line of research will be to study the atmosphere of the planet K2-237 b, "that will not be immediate, but we hope that data will be obtained for that purpose shortly," concludes the astronomer, also a postdoctoral researcher at the University of London Queen Mary.

The work involved a dozen scientists including: Maritza Soto (first author of the paper and who was in charge to collect all data and analysis, and interpret the results obtained, in addition to calculating some of the parameters of the stars) , James Jenkins, academic of the Department of Astronomy FCFM of the University of Chile and Andrés Jordan, academic of the Institute of Astrophysics UC, the last two also researchers of the Center of Astrophysics CATA.