Temperature

From OGame Wiki

Each planet has a specific maximum and minimum planet temperature depending on the planet's slot. The planets with the highest temperatures are closer to the sun. Also, the power generated from a Solar Satellite rises with the planets maximum temperature (up to a maximum output of 52 per satellite), while the production of Deuterium Synthesizers falls. The lower the temperature, the more deuterium per hour you get (see Deuterium Synthesizer for formula).