Stellarium: My new favourite toy

I’ve been playing around with Stellarium for most of the weekend and finding it utterly fascinating. The program is a free and open-source planetarium that runs under Linux, Windows or Mac OSX and it shows you a realistic 3D view of the night sky. This is impressive in itself and provides a useful tool for deciding which are the best nights to take your binoculars outside. But there is much more to it than this.

As well as allowing you to select any location on Earth, Stellarium also allows you to pick locations elsewhere in the Solar System. This is the closest I will ever get to standing on Mars and watching the Earth rise and, even virtually, it’s a stunning sight.