PLANETS AND MOONS

Before the space revolution, planets were hardly more when dots in the sky that revealed blurred details when seen through telescopes. Now, thanks to surveys by diligent spaces probes, planets are real " new worlds " with mountains, valleys, volcanoes, ring system, and vast entourage of moons. Even the moons have their own personalities, from Triton with its ice volcanoes to Europe, which may be covered, by a warm ocean containing lifeforms. Only remote Pluto has not been visited, but even that is on the cards. Space probes and astronauts too, have also greatly increased what we know about our own planet and its Moon, helping to set them in context among their neighbor. But the planet most under scrutiny is Mars, which will almost certainly receive a visit from a human crew within our lifetimes.