Corot-7b is an exoplanet that has captivated astronomers since its discovery in 2009. Located approximately 490 light-years away in the constellation Monoceros, it was the first rocky planet discovered outside our solar system, paving the way for studies of terrestrial exoplanets. This “super-Earth” is known for its extreme environment, which includes temperatures high enough to melt rock and possible volcanic activity.
The planet was discovered by the French-led CoRoT (Convection, Rotation, and Planetary Transits) mission, which identified it using the transit method. This technique measures the dimming of a star’s light when a planet passes in front of it, providing valuable information about the planet’s size and orbit. Corot-7b was a groundbreaking find because it confirmed that rocky planets like Earth exist beyond our solar system.
Corot-7b is about 1.6 times the size of Earth and approximately 4.8 times its mass. While its rocky composition makes it similar to Earth, the planet is far from hospitable. It orbits its star at an incredibly close distance—just 2.5 million kilometers (1.5 million miles)—completing a full orbit in only 20 hours. This proximity exposes Corot-7b to intense stellar radiation, resulting in surface temperatures that range from 1,980°C (3,600°F) on the day side to possibly freezing temperatures on the night side.
The extreme heat on the day side likely causes surface materials to vaporize, creating a “rock vapor” atmosphere that condenses into molten rock rain. These conditions have led scientists to theorize that Corot-7b may be covered in vast oceans of lava, making it one of the most volcanically active planets known.
Despite its harsh environment, Corot-7b is significant for what it reveals about planetary formation and evolution. Its proximity to its star suggests that it may have once been a gas giant, with its atmosphere stripped away over time by intense stellar radiation, leaving behind a rocky core.
Corot-7b’s discovery marked a milestone in exoplanet research and continues to inspire questions about the diversity of planets in the universe. While it is unlikely to support life, studying this volcanic world helps scientists understand the range of conditions planets can endure and the factors that influence their development.