HD 190622 (TOI-1054) light and RV curves

These provide insight into properties like the amount of volatiles, which in turn can be related to formation and evolution processes. The TESS mission reported a planetary candidate around HD 190622 (TOI-1054) which was subsequently validated and which deserved further characterization with photometric and spectroscopic facilities. The KESPRINT collaboration used HARPS data to independently confirm the planetary candidate, securing its mass, and revealing the presence of an outer giant planet in the system.

The CHEOPS consortium invested telescope time in the transiting target in order to reduce the uncertainty of the radius, improving the characterization of the planet. We present the discovery and characterization of the planetary system around HD 190622 (TOI-1054), a system hosting one transiting planet which is smaller than Neptune (3.087^+0.058^_-0.053_R_Earth_, 7.7+/-1.0M_Earth_) but has a similar bulk density (1.43+/-0.21g/cm^3^) and an orbital period of 16 days; and a giant planet, not known to be transiting, with a minimum mass of 227.0+/-6.7M_Earth_ in an orbit with a period of 315 days.

Our measurements constrain the structure and composition of the transiting planet. HD 190622b has singular properties among the known population of transiting planets that we discuss in detail. Among the sub-Neptune-sized planets known today, this planet stands out because of its large gas content.