found near the star HD 27894
According to recent observations, the giant planet HD 27894 b has two massive satellites. One with the mass of Saturn, and the second - the cold world, more than Jupiter several times.
HD 27894 removed for 138 light years. This is an inactive star of the solar type (K2V), which is 20% less massive than the Sun. Planet HD 27894 b was discovered in 2005 when measuring radial velocities at the La Silla Observatory.
The apparent size of the star is 9.36, and the rotation frequency reaches 44 days. That is why it has become an attractive target for HARPS. After the discovery of the planet, scientists continued to survey the spectrograph in 2006, 2013 and 2016.
Images a and b show the signals of planets HD 27894 b and c, whose periodicity lasts 18 and 36 days. In the picture c, the Doppler signal is displayed, and d is the residual 3PKM Recently, a group of scientists led by Trifon Trifonov analyzed information and found additional planets in the system. It turned out that two gas giants revolve around the star. The HD 27894 mass reaches 0.16 times Jupiter, the orbital period lasts 36 days, and the distance from the star is 0.2 a. e. HD 27894 d located at 5.5 a. e., mass exceeds Jupiter 5.4 times, and spends 14 years on the orbital passage.
This is a unique system and the placement of the planets can tell a lot about its evolution. Scientists believe that the internal pair could form in another place, and then simply attracted the star's gravity. An interesting assumption regarding the outer planet, since it could migrate further after the disk evaporated.
