Venus

The second planet from the Sun

Nearly Earth's twin in size and mass, and the planet that comes closest to us, Venus lies hidden under clouds of sulphuric acid. Beneath them is a runaway greenhouse: an atmosphere of carbon dioxide 92 times as heavy as ours and a surface at 464 °C, hotter than Mercury's.

It turns backwards, and so slowly that one turn takes 243 of our days, longer than its 225-day year, while its clouds race round it in four. They can be lifted here to show the ground as NASA's Magellan probe mapped it by radar in the early 1990s: the highlands of Ishtar and Aphrodite, Maxwell Montes, and the sites where the Soviet Venera and Vega landers came down.