Today is the most important day in the flight of the European Space Agency Probe Venus Express since its launch from Baikonur in Kazakhstan last November. After a long but uneventful journey across 400 million kilometres of space, the capsule will this morning use its main engine to slow down and enter an orbit around the planet Venus.The capsule should be captured by the gravitational pull of Venus – the second nearest planet to the Sun – at around 0917 CET this morning. It is hoped Venus Express will provide valuable information about the crust and atmosphere on the planet, known as Earth’s twin sister. Despite its connotations of beauty, Venus is one of the most inhospitable planets in our galaxy. With temperatures of 460 degrees celsius on the surface, the atmosphere is composed of noxious acids stirred by 400 kilometre an hour winds. Venus Express will spend 486 earth days – equivalent to only two Venus days – orbiting the planet and gathering information.