The HIP 91258 Exoplanetary System
HIP 91258 is a star with 0.97 times the mass of the Sun, and 0.89 times its radius. It is located 149.87 light years away from the solar system.
HIP 91258 is known to have 1 exoplanets in orbit around it.
HIP 91258 b
HIP 91258 b was discovered by the Haute-Provence Observatory observatory using the radial velocity method. Its discovery was announced in 2014-03. Its semi-major axis is 0.06 astronomical units, as compared to Earth's which is 1 astronomical unit. It takes 5.05 Earth days to complete an orbit around its host star, HIP 91258.
Its eccentricity, the extent to which the shape of the exoplanet's orbit departs from a perfect circle (Earth's is 0.0167, which is why the shape of Earth's orbit is circular rather than oval in appearance), is 0.02, which means that when HIP 91258 b is at is at its closest point to its host star, 0.06 astronomical units separates the two, and when it is at its farthest point, this number is 0.06. In the case of Earth, these numbers are 0.9832899 and 1.0167103 respectively.
The mass of HIP 91258 b is 346.41 times the mass of Earth. At more than 50 Earth masses, HIP 91258 b is a gas giant, a planet whose mass is mostly made up of hydrogen and helium, like Jupiter and Saturn in our solar system.