Mullard Radio Astronomy Observatory: UK March 2012/October 2014

MRAO is home to a selection of large aperture synthesis radio telescopes.

What you see here is the One Mile Telescope, the half mile telescope, the 4C array, the Cosmic Anistropy Telescope and one reciever from Merlin array.

The One Mile Telescope

The One Mile telescope was constucted in 1964 and was used to produce the 5C catalogue of radio sources. It is made up of three 60 foot parabolic reflectors, which are fully steerable. Each dish weighs in at 120 ton. Two are fixed and one is set on an 800m track with the Half Mile Telescope. This track is straight to within 0.9cm and is raised 5cm at the far end to allow for the curvature of the Earth. This set up was able to observe indivdual radio sources at extreme sensitivity, angular resolution and image quality. These surveys required intensive use of inverse Fourier transform. Development of new a generation of computers such as the Titan made this possible.

The Half Mile Telescope

The Half Mile Telescope originally constructed in 1968 consisted of two dishes. In 1972 two more dishes were added. Two are fixed and two share the track with the One Mile Telescope. Thirty days of observing were required to obtain information from the maximum number of different baselines. They produced the first good radio maps of hydrogen distribution for the Triangulum Galaxy (M33) and the Andromeda Galaxy (M31).

The 4C Array

The 4C Array which looks like a huge aerial is a cylindrical paraboloid radio telescope. It was constructed in 1958 and used 64km of reflector cable! It is 450m long and 20m wide. There was also a second moveable element which has mostly been removed.

The Cosmic Anistropy Telescope

The Cosmic Anistropy Telescope enlosure which is just like a huge bowl set in the ground was built in 1995. It was a three-element inerferometer for cosmic microwave background radiation observations at 13 to 17 GHZ. All three antennas were mounted on a single turntable which tracked in azimuth, and had a separate elevation drive. The first results, published in 1996, were the highest resolution CMB detection at that time. It was partly dismantled in 2000