HD 202772 A and Its Lone Known Planet

HD 202772 A is a star 527 light-years away with one known planet in its cataloged system. The star is 1.63 billion years old, with a mass of 1.72 solar masses and a radius of 2.55 solar radii. Its temperature is 6440 K, and its reported mass, radius, and temperature estimates are all larger or hotter than the Sun's.

The planet HD 202772 A b was discovered in 2019 by the transit method, in which a planet passes in front of its star from our viewpoint and causes a small dip in observed brightness. Repeated dips help establish orbital periods. The planet is classified as Jupiter-like, meaning its radius exceeds 4 times Earth's radius. Its radius is 18.2 Earth radii, and its mass is 324 Earth masses; both estimates are larger than Earth's. It completes an orbit in 3.31 days. Its mean density is 0.294 g/cm³, which is 0.0533 times Earth's.