Kepler-36b is an

exoplanet An exoplanet or extrasolar planet is a planet outside the Solar System. The first confirmed detection of an exoplanet was in 1992 around a pulsar, and the first detection around a main-sequence star was in 1995. A different planet, first det ...

orbiting the star Kepler-36. This planet has the closest conjunction to Kepler-36c every 97 days. Its density is similar to that of

iron Iron is a chemical element; it has symbol Fe () and atomic number 26. It is a metal that belongs to the first transition series and group 8 of the periodic table. It is, by mass, the most common element on Earth, forming much of Earth's o ...

. During their closest approach, Kepler-36b and Kepler-36c are located only 0.013 AU (about 1,900,000 km) from each other, which causes extreme transit-timing variations for both planets. Transit-timing variations caused by Kepler-36c are strong enough to put narrow constraints on Kepler-36b's mass. The close proximity of the planet to its host star combined with its relatively low mass caused the planet to lose all or most of its primordial hydrogen/helium envelope.

References

Cygnus (constellation) 36b Exoplanets discovered in 2012 {{extrasolar-planet-stub