When you look up into the sky at night you see the stars as pretty twinkling lights. An astronomer admires the beauty of the stars and other celestial objects and wants to learn what they are and how they work. An astronomer is a scientist who tries to understand and interpret the Universe beyond Earth and the Earth within the Universe.

   Using observational tools like space and ground-based observatories, computers and the good old paper and pencil, astronomers attempt to build up a picture, not only of what the Universe is like today, but what it was like billions of years ago, right back to the “Big Bang”. To do this Astronomers have to understand the behaviour of matter in conditions that simply do not exist on Earth, whether at extreme temperatures or involving exotic objects and particles.

   They must use whatever kind of light, from radio to gamma rays, and particles (from cosmic rays to neutrinos) make it....