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 from 01/10 2007 to 30/06 2009, offered all house owners in NSW a rebate on systems that were replacing existing electric hot water systems. The more efficient the system (emitting less Greenhouse gas), the more RECs the system was eligible for, generating a higher rebate. Power and Water Corporation, the principal water and electricity supplier in the Northern Territory, offers an REC buyback scheme on installations of solar water heaters. The buyback must be applied for and assigned less than one year after the installation. The Queensland Government's Solar hot water rebate scheme finished on 30 June 2005. No state