Kepler-63
Kepler-63 is a G-type main-sequence star about 638 light-years away. The star is much younger than the Sun, at. Kepler-63 is similar to the Sun in its concentration of heavy elements.
The star is exhibiting strong starspot activity, with relatively cold starspots concentrated in two mid-latitude bands similar to the Sun, changing their position in a cycle with a period of 1.27 years. Due to high magnetic activity associated with its young age, Kepler-63 has a very hot corona heated to 8 million degrees, and produces over ten times the solar amount of x-rays than the Sun.
Multiplicity surveys did not detect any stellar companions to Kepler-63 by 2016.