Mercury (planet) Mercury (planet) Mercury is the smallest and innermost planet in the Solar System. Its orbital period around the Sun of 87.97 days is the shortest of all the planets in the Solar System. It is named after the Roman deity Mercury, the messenger of the gods. Like Venus, Mercury orbits the Sun within Earth's orbit as an "inferior planet", and never exceeds 28° away from the Sun. When viewed from Earth, this proximity to the Sun means the planet can only be seen near the western or eastern horizon during the early evening or early morning. At this time it
Solar power in Spain The Andasol 1 power plant went online in November 2008, and has a thermal storage system which absorbs part of the heat produced in the solar field during the day. This heat is then stored in a molten salt mixture and used to generate electricity during the night, or when the sky is overcast. A 15 MWe solar-only power tower plant, the Solar Tres project, is in the hands of the Spanish company SENER, employing molten salt technologies for receiving and energy storage. Its 16-hour molten salt storage system will be able to deliver power around the clock. The Solar