An international team of astronomers reports the discovery of two new “super-Earths” exoplanets orbiting a nearby M-type dwarf star.
These newly discovered alien worlds, called LP 890-9 b and LP 890-9 c, are slightly larger than Earth, and the discovery was published in the Journal of Astronomy and Astrophysics.
“Super planets” are planets larger than Earth, but do not exceed the mass of Neptune, and although the term “super-Earth” refers only to the mass of the planet, it is also used by astronomers to describe planets larger than Earth, but smaller than the so-called Little Neptune.
The radius of (LP 890-9 b) is about 1.32 the radius of the Earth, and its mass is estimated to be no more than 13.2 Earth masses, and the planet revolves around its host every 2.73 days at a distance of about 0.018 astronomical units from it.
As for the asteroid (LP 890-9 c), its radius was measured to be about 1.37 Earth’s radius, while its mass is assumed to be less than 25.3 Earth masses, 0.04 AU away from its original star, and its orbital period is about 8.46 days.
The host star of the two planets (LP 890-9), has a radius of about 0.15 solar radii and a mass of 0.12 solar masses. The effective temperature of this M dwarf is about 2871 K, and the star is located about 104 light years from Earth.
Summing up the results, the astronomers confirmed that their discovery makes the star (LP 890-9), the second coolest star found to host planets, and they added that it is the second most terrestrial habitable planet known to date.
The authors of the paper conclude that “the discovery of the remarkable (LP 890-9) system presented in this work provides another rare opportunity to study temperate terrestrial planets around our smallest and most magnificent neighbours.”