These are artistic representations of all the planets around other stars (exoplanets) with any potential to support surface life as we know it. All of them are larger than Earth and we are less certain about their composition and habitability, but they represent the best objects of interest for future observations. They are ranked from best to worst with the Earth Similarity Index (ESI), a measure of Earth-likeness, but none yet seems to be a true Earth-like planet. This selection of worlds is also subject to change as new interpretations or astronomical observations are made. Earth, Mars, Jupiter, and Uranus are shown for scale on the right. Planetary Names: Welcome. Extrasolar-planets.com. The Extrasolar Planets Encyclopaedia. Exoplanet Orbit Database. Portal. Home.