Planet
The smallest known planet is PSR B1257+12A, one of the first extrasolar planets discovered, which was found in 1992 in orbit around a pulsar. Its mass is roughly half that of the planet Mercury. The smallest known planet orbiting a main-sequence star other than the Sun is Kepler-37b, with a mass (and radius) slightly higher than that of the Moon.
List of nearest exoplanets
Most known nearby exoplanets orbit close to their star and have highly eccentric orbits. A majority are significantly larger than Earth, but a few have similar masses, including two planets (around YZ Ceti, 12 ly) which may be less massive than Earth. Several confirmed exoplanets are hypothesized to be potentially habitable, with Proxima Centauri b and three around Gliese 667 C (23.6 ly) considered the most likely candidates. The International Astronomical Union took a public survey in 2015 about renaming some known extrasolar bodies, including the planets around Epsilon Eridani (10.5 ly) and Fomalhaut.