Kepler-23
Kepler-23 is a G-type [main-sequence star] about away in the northern constellation of Cygnus, the swan. With an apparent [visual magnitude] of 13.5, it is too faint to be seen with the naked eye. This star is similar in mass and temperature to the Sun, but is larger and more luminous. Kepler-23 is orbited by three known exoplanets.
Three transiting exoplanets orbit this star, discovered using the Kepler space telescope. Two planets, Kepler-23b and Kepler-23c, were discovered in 2011 and were confirmed in 2012. A third planet, Kepler-23d, was confirmed in 2014 as part of a study validating hundreds of Kepler candidates. All three planets are between Earth and Neptune in size, and their masses have been measured via transit-timing variations, showing that they have lower densities than Earth.