K2-3d
| Size comparison between the Earth and K2-3d. | |
| Discovery | |
|---|---|
| Discovery site | Kepler Space Observatory | 
| Discovery date | 2015 | 
| Transit | |
| Orbital characteristics | |
| 0.2014+0.0034 −0.0033 AU | |
| Eccentricity | 0.091+0.120 −0.064 | 
| 44.55603+0.00013 −0.00012 d | |
| Inclination | 89.788°+0.033° −0.029° | 
| Semi-amplitude | <0.39 m/s | 
| Star | K2-3 | 
| Physical characteristics | |
| 1.458+0.056 −0.051 R🜨 | |
| Mass | <1.6 M🜨 | 
| Mean density | <2.1 g/cm3 | 
| Temperature | 305.2+3.1 −3.2 K (32.1 °C; 89.7 °F, equilibrium) | 
K2-3d, also known as EPIC 201367065 d, is a confirmed exoplanet of probable mini-Neptune type orbiting the red dwarf star K2-3, and the outermost of three such planets discovered in the system. It is located 143 light-years (44 parsecs) away from Earth in the constellation of Leo. The exoplanet was found by using the transit method, in which the dimming effect that a planet causes as it crosses in front of its star is measured. It was the first planet in the Kepler "Second Light" mission to receive the letter "d" designation for a planet. Its discovery was announced in January 2015.