Nasa astronauts have successfully completed their third spacewalk in just over a week to finish an extensive cable job at the International Space Station.

NASA astronauts have successfully completed their third spacewalk in just over a week to complete an extensive cable job at the International Space Station.

Test your knowledge of science and nature with our tricky multiple choice quiz. Then find out how bright you are. (Answers are at the bottom — but no peeking!

A SPACECRAFT that made history in 2005 by firing a torpedo probe into a comet is setting off on a 1.6 billion mile journey across the solar system.