HD 224018 and Its Three Planets

HD 224018 is a G V star, a Sun-like main-sequence dwarf, located 344 light-years away. The star is 7 billion years old, with a reported mass of 1.01 solar masses, a radius of 1.15 solar radii, and a temperature of 5780 K. Its reported radius estimate is larger than the Sun's. Three planets are known to orbit this host.

HD 224018 b is a Sub-Earth discovered by the radial velocity method in 2025, which measures the wobble a planet's gravity induces in its star's motion. It has a mass of 4.1 Earth masses, a radius of 0.91 Earth radii, and an orbital period of 10.6 days. Among the listed planets, it has the shortest year, the smallest radius, and the smallest reported mass by reported estimates.

HD 224018 c is a Super-Earth discovered by the transit method in 2025, which detects the small dip in a star's brightness when a planet passes in front of it. It has a mass of 10.4 Earth masses, a radius of 2.42 Earth radii, and an orbital period of 36.6 days. Among the listed planets, it has the largest radius and the largest reported mass by reported estimates, and its year is the second-shortest.

HD 224018 d is a Super-Earth also discovered by the transit method in 2025. It has a mass of 4.2 Earth masses, a radius of 2.4 Earth radii, and an orbital period of 138 days. Among the listed planets, it has the longest year, the second-smallest radius, and the second-smallest reported mass by reported estimates. All three planets have reported mass and radius estimates larger than Earth's, and their estimated mean densities are 30 grams per cubic centimeter for HD 224018 b, 4.04 grams per cubic centimeter for HD 224018 c, and 1.67 grams per cubic centimeter for HD 224018 d.