That’s a big one!

NASA has put on show a full-size model of the really rather impressive James Webb Space Telescope, which is due to be launched in 2013.

The main mirror of the JWST will have a diameter of 6.5 metres – which is enormous compared to any previous space instrument. It’s even bigger than the famous 200 inch reflector, which was the biggest telescope in the world for many years.

Seriously. Impressive. Engineering.