The Andromeda Galaxy Copyrighted image Credit: By Davidherraezcalzada via Dreamstime under subscription

In the third episode of the series that puts science and technology to the test, the team face more fun experiments and challenges. And why not join in with our debate on the size of the universe: read Dr Andrew Norton's article below, which may help you get your head round just how big, big can be!

Tonight Liz conducts an experiment into jet lag and how to avoid it.

Dallas demonstrates the size of the solar system with the help of a bicycle and a fruit bowl.

And Jem upgrades his square-wheeled skateboard.

First broadcast on 22 September 2010

Inside the science

Solar size

Jeg lag

Sensory receptors

Square-wheeled motorbike