Kepler-1963 b: A Sub-Earth

Kepler-1963 is a star located 1610 light-years away, and one planet has been reported in its orbit. The host star is estimated to be 4.07 billion years old, with a mass of 0.857 solar masses and a radius of 0.814 solar radii. Its reported temperature is 5440 K. Its reported mass and radius estimates are smaller than the Sun's, and its reported temperature is cooler than the Sun's.

The system's only known planet, Kepler-1963 b, was discovered in 2021 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, and Kepler-1963 b completes one orbit every 1.96 days. Its radius is 0.744 Earth radii, making it a Sub-Earth, a size class for planets smaller than Earth. That radius is smaller than Earth's.