Transiting Exoplanet with Longest Known Year

This artist's conception shows the Uranus-sized exoplanet Kepler-421b, which orbits an orange, type K star about 1,000 light-years from Earth. Kepler-421b is the transiting exoplanet with the longest known year, circling its star once every 704 days. It is located beyond the "snow line" – the dividing line between rocky and gaseous planets – and might have formed in place rather than migrating from a different orbit.


David A. Aguilar (CfA)