TOI-2076 and Its Four Planets

TOI-2076 is a K-type star located 137 light-years away. Its reported mass is 0.85 solar masses, its radius is 0.762 solar radii, and its temperature is 5190 K. Its age is 0.204 billion years. Both the star's mass and radius estimates are smaller than the Sun's, and its temperature is cooler than the Sun's. Four planets are known to orbit this star, all discovered by the transit method, in which a planet passing in front of its star from our viewpoint causes a small dip in observed brightness.

TOI-2076 b is a Neptune-like planet discovered in 2021. Its mass is 6.7 Earth masses, its radius is 2.59 Earth radii, and its orbital period is 10.4 days. Its mean density is 2.12 g/cm³, 0.386 times Earth's.

TOI-2076 c is also Neptune-like, discovered in 2021. Its mass is 7.2 Earth masses, its radius is 3.54 Earth radii, and its orbital period is 21 days. Its mean density is 0.894 g/cm³, 0.162 times Earth's.

TOI-2076 d, another Neptune-like planet found in 2021, has a mass of 7.3 Earth masses, a radius of 3.27 Earth radii, and an orbital period of 35.1 days. Its mean density is 1.15 g/cm³, 0.209 times Earth's.

TOI-2076 e is an Earth-like planet discovered in 2025, with a mass of 4.7 Earth masses, a radius of 1.3 Earth radii, and an orbital period of 3.02 days. Its mean density is 11.8 g/cm³, 2.13 times Earth's.

Each of the four planets has a reported radius and mass larger than Earth's. Among the listed planets, TOI-2076 e has the shortest year by reported estimates, 3.02 days, while TOI-2076 d has the longest, 35.1 days. TOI-2076 e also has the smallest radius, 1.3 Earth radii, and the smallest reported mass, 4.7 Earth masses. TOI-2076 c has the largest radius, 3.54 Earth radii, and TOI-2076 d has the largest reported mass, 7.3 Earth masses.