11.04.13 – The analysis of the first three years of Kepler data have revealed more than 3,600 candidate worlds. The diagram plots the planet candidates by oribtal period on the x-axis and size relative to Earth on the y-axis. The majority of Kepler’s detections are of smaller sized worlds less than three times the size of Earth. Previous to Kepler’s search, the majority of discoveries where of large planets the size of Jupiter or greater in very tight orbits around their star, the so-called hot Jupiters. From Kepler we know that most stars harbor at least one planet and that small planets the size of Earth are common in the galaxy, providing more possiblities to search for life.
Read more about the discovery here: https://www.nasa.gov/content/nasa-kepler-results-usher-in-a-new-era-of-astronomy.
Credit: NASA Ames/W. Stenzel