Mercury (planet) 2015. The "BepiColombo" spacecraft will arrive at Mercury in 2025. Mercury appears to have a solid silicate crust and mantle overlying a solid, iron sulfide outer core layer, a deeper liquid core layer, and possibly a solid inner core. Mercury is one of four terrestrial planets in the Solar System, and is a rocky body like Earth. It is the smallest planet in the Solar System, with an equatorial radius of . Mercury is also smaller—albeit more massive—than the largest natural satellites in the Solar System, Ganymede and Titan. Mercury consists of approximately 70% metallic and 30% silicate material. Mercury's
Solar hot water in Australia rebates are offered at the present, however the Queensland government in 2007 announced the phasing-out of electric hot water systems commencing in 2010. From 2010, Queenslanders who need to replace their household hot water system due to breakdown will no longer be able to install electric systems, and will instead have to choose from gas, solar or heat pump options. Prior to this, the Queensland government had already banned the installation of electric hot water systems in newly constructed houses; a law which came into effect on 1 March 2006. The ban on electric hot water systems was repealed on