Properties of low-mass stars and planets

Illustration of the properties of low-mass stars and planets, expressed in solar units. The newly determined, precise values of the mass and radius of OGLE-TR-122b are indicated as the red dot. The blue symbols are values for low-mass stars, while the black symbols on the left represent exoplanets. Note that the "hot Jupiters" — exoplanets orbiting very close to their host star — are larger than OGLE-TR-122b. The various lines represent theoretical models from G. Chabrier, I. Baraffe and colleagues, showing a good agreement between theory and observations.