Terrestrial planet Terrestrial planet A terrestrial planet, telluric planet, or rocky planet is a planet that is composed primarily of silicate rocks or metals. Within the Solar System, the terrestrial planets are the inner planets closest to the Sun, i.e. Mercury, Venus, Earth, and Mars. The terms "terrestrial planet" and "telluric planet" are derived from Latin words for Earth ("Terra" and "Tellus"), as these planets are, in terms of structure, "Earth-like". Terrestrial planets have a solid planetary surface, making them substantially different from the larger giant planets, which are composed mostly of some combination of hydrogen, helium, and water existing in various
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 The ban on electric hot water systems was repealed on