Assembly of the Azimuth Ring

The design of a telescope must allow the instrument to point at any part of the night sky. To do this it must be able to move in two axes. The Liverpool Telescope, like all modern professional astronomical telescopes, can turn round (horizontal movement) and look up and down (vertical movement).

The telescope moves round on the azimuth axis and up and down on the altitude axis. The telescope has what is called an altazimuth mounting. Watch the animation (right) and you can see the movements the telescope makes on these two axes.

The azimuth ring is lifted onto the circle of fixators already firmly attached to the concrete base and the sequence of pictures below show this process.

assembling the azimuth ring

assembling the azimuth ring

assembling the azimuth ring

Care is taken to see that everything fits correctly.

Before this stage of assembly is finished it is important that the azimuth ring is carefully levelled. This is done so accurately that the surface is level within the thickness of a human hair.

The twelve fixators keep the azimuth ring well supported and each one must be adjusted until everything is level.

You can see the finely machined surface of the azimuth ring in the right hand picture with the spirit level being used for level adjustments. On this surface the whole weight of the telescope acts with a thin film of oil separating surfaces of metal which smoothly glide over one another as the telescope moves.

The last picture below shows the azimuth ring finally in place on the concrete base with the oil tray around the outside.

The next task is to assemble and test the hydrostatic bearings which run on top of the azimuth ring. Our next news bulletin will describe these bearings and show their assembly.