Astronomers have found super-mercury and cold Jupiter around a solar-type star solar type HD 137496 with an age of 8.3 billion years. Both objects have been identified as hot super-mercury and cold Jupiter. Details of the discovery are presented in an article available in the arXiv.org preprint repository.
The planets were identified by the Kepler Space Telescope, which has detected more than 2,600 exoplanets to date. The discovery was made when the telescope observed HD 137496 as part of the K2 mission from August 23, 2017 to November 19, 2017. Scientists have identified transit signals on the light curve of HD 137496, arising when an object passes against the background of the star's disk, and determined their planetary nature.
The closest exoplanet HD 137496 b is about 30 percent larger than Earth and approximately four times more massive than her. This planet is composed primarily of iron, and the core makes up over 70 percent of the object's mass. HD 137496 b revolves around the parent star every 1.62 days at a distance of about 0.027 astronomical units (one AU is equal to the average distance from the Sun to the Earth), and the equilibrium temperature is estimated at about 2130 Kelvin.
Second the exoplanet received the designation HD 137496 c. It has been classified as a cold Jupiter with a minimum mass of about 7.66 Jupiter's masses, and its equilibrium temperature is estimated at about 370 Kelvin. The planet revolves around HD 137496 in a highly eccentric (elongated) orbit every 480 days at a distance of 1.21 AU. from the star.