Kepler-199 and Its Two Neptune-Like Worlds

Kepler-199 is a star located 1700 light-years away, and it hosts two known planets. The star is 1.45 billion years old, with a mass of 0.96 solar masses and a radius of 0.88 solar radii. Its temperature is 5710 K, and its mass and radius are both smaller than the Sun's.

Both planets were discovered by transit in 2014, the 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 time a planet takes to complete one orbit.

Kepler-199 b is a Neptune-like planet with an orbital period of 23.6 days and a radius of 3.11 Earth radii, larger than Earth's. Kepler-199 c is also Neptune-like, with an orbital period of 67.1 days and a radius of 3.25 Earth radii, also larger than Earth's.

Among the listed planets, Kepler-199 b has the shortest year and the smallest radius by reported estimates, at 23.6 days and 3.11 Earth radii. Kepler-199 c has the longest year and the largest radius by reported estimates, at 67.1 days and 3.25 Earth radii.