Telescope component viewed close up
BBC correspondent Jonathan Amos goes to the Rutherford Appleton Laboratory in Oxfordshire to see the Mid-Infrared Instrument (Miri) close up, just before it is shipped to Nasa in the US.
The instrument will form a critical part of the James Webb Space Telescope, the successor to Hubble.
Here we see him suiting up prior to entering the clean room where he explains what the instrument will do.
He then heads to the test chamber where Miri was subjected to conditions similar to those it will encounter in space.