55 Cancri e is one of the planet of the star 55 Cancri A. It has a mass nearly eight times the Earth, about half the mass of Neptune. The diameter of 55 Cancri e is about twice the Earth. Its orbital period is just about 18 days and the estimated surface temperature is about 1800 degrees Celsius (3200 degrees Fahrenheit). The extraordinary thing is that given the temperature and pressure existing on the surface of the planet it’s likely that various compounds are supercritical fluids.