Did A Mega-collision Alter Venus?NASA radar image of Venus. (Credit: JPL, NASA) ScienceDaily (Feb. 27, 2008) — A mega-collision between two large embryonic planets could have created Venus as we know it, according to a new paper by a Cardiff University scientist. Venus is a sister planet to Earth. It is nearly the same size and density yet it has a surface temperature of 720 K, an atmosphere dominated by carbon dioxide and no evidence of oceans or ridges. It has been described as “Earth’s evil twin”. Dr Huw Davies, of the School of Earth and Ocean Sciences argues that...