Shooting star trails over the Arcminute Array at Cambridge University

A few months ago I decided to venture down to Cambridge to shoot star trails over various radio telescopes in an area of land owned by Cambridge University. A fellow photographer had offered to take me behind the locked gates with a permission visit. I'm not one to refuse such an opportunity so I jumped at the chance.

Cambridge University operates the Mullard Radio Astronomy telescopes aka MRAO, some of which recently became redundant and subsequently my subject for the evening.

We parked in the agreed meeting place and walked in to the site for over a mile. The radio telescopes are enclosed inside a metal structure with angled walls presumably to filter out interference and which also has a metal grid floor throughout.

To enter the square structure is one single, huge door which hangs at the same angle as the walls. Our aim was to capture star trails over a 2 hour period which meant we had to set up the cameras running inside and leave the structure with the doors closed.

Conveniently for me, the whole array of telescopes faces due north which made it very easy to align Polaris aka The North Star.

Star Trails over the Array

The array of telescopes is formally known as the Arcminute Microkelvin Imager Small Array. You can always trust a scientist to come up with a catchy name!

This is 319 x 20 second exposures. I couldn't resist lighting it up.