MOA-2007-BLG-192L
The discovery of a planet, MOA-2007-BLG-192Lb, orbiting this object was announced on June 2, 2008. This planet, with a mass of approximately 3.3 times that of Earth, is one of the smallest known extrasolar planets. It was found when it caused a gravitational microlensing event on the night of May 24, 2007, which was detected as part of the MOA-II gravitational microlensing survey at the Mount John University Observatory in New Zealand.
John Johnson (astronomer)
In 2012, Johnson's team discovered three small rocky exoplanets in a red dwarf star system observed with the Kepler space telescope. The system was renamed Kepler-42 and the outermost planet was found to be nearly as small as Mars, making it the smallest known exoplanet at the time. A subsequent study used the host star's similarity to Barnard's Star and observations from the Keck Observatory to more precisely measure the properties of the system, including the sizes of the three planets.