Torbjörn Sassersson är grundare av NewsVoice som startade 2011. Torbjörn har arbetat inom media sedan 1995. Han har en fil kand (1992) inom miljövård från Stockholms Universitet. Stöd hans arbete genom en 
Guardian.co.uk: Nasa discovers planet that is about 2.4 times the size of our own and lies in the ‘Goldilocks zone’ of its solar system.
A new planet outside Earth’s solar system has been identified with many similarities to our own – making it the latest best potential target for life. Kepler 22-b, which is about 2.4 times the size of Earth and lies in the so-called “Goldilocks zone”, has a relatively comfortable surface temperature of about 22C (72F) and orbits a star not unlike Earth’s sun.
Wikipedia: The discovery was announced December 5, 2011. The planet’s radius is roughly 2.4 times the radius of Earth; it is 600 light years away from Earth, in orbit around the G-type star Kepler 22.
The distance from Kepler-22b to its star is about 15% less than the distance from Earth to the Sun. Its orbit is about 85% as large as Earth’s orbit. One orbital revolution around its star takes 289.9 days.
The light output of Kepler-22b’s star is about 25% less than that of the Sun.
The combination of a shorter distance from the star and a lower light output are consistent with a moderate surface temperature. Scientists estimate that in the absence of atmosphere, the equilibrium temperature would be approximately -11°C. If the greenhouse effect caused by the atmosphere is Earthlike, this corresponds to approximately 22 °C (72°F) average surface temperature.