Stargazers could enjoy a rare spectacle as a bright comet swings into the Northern Hemisphere. The icy mass, called C/2011 L4 Pan-Starrs, should be visible with binoculars or a telescope from 8 March.
No need to carry around heavy equipment, demonstrate conservation of momentum easily with this Newton's Cradle app, using your device's accelerometer to get those balls swinging! Suitable for Android users.