Physics KS3 / GCSE: Light and looking back in time

Professor Brian Cox explains that light is the fastest thing in the Universe, but it’s not infinitely fast; so the further an object is from us, the further back in time we see it.

He outlines that the light we see from the Sun left its surface 8 minutes ago, and the light from our nearest galaxy, Andromeda, is 2.5 million years old.

The Hubble Ultra Deep Field space telescope has taken pictures of a piece of space which is so far away the light has taken 13 billion years to reach us.

This clip is from the series Wonders of the Universe.

Teacher Notes

This clip could be used to initiate discussion of the vast distances involved in space travel and why this presents a problem for manned missions to even relatively close bodies such as Mars.

Curriculum Notes

These clips will be relevant for teaching Physics at KS4 and GCSE in England, Wales and Northern Ireland and National 4/5 or Higher in Scotland.

The topics discussed will support OCR, Edexcel, AQA, WJEC GCSE in England and Wales, CCEA GCSE in Northern Ireland and SQA National 4/5 and Higher in Scotland.