The World’s Biggest Eye on the Sky (E-ELT)
Report and photograph by L. Trollope.

“EXTREMELY Large Telescopes are considered worldwide as one of the highest priorities in ground-based astronomy. They will vastly advance astrophysical knowledge, allowing detailed studies of subjects including planets around other stars, the first objects in the Universe, super-massive black holes, and the nature and distribution of the dark matter and dark energy which dominate the Universe”, said Dr Gerard Gilligan, the Hon. Secretary of Liverpool Astronomical Society. So it was a privilege to attend the latest monthly meeting of the society, on April 15, 2011, and to hear a fascinating talk given by Professor David Walker on this subject. Professor Walker is poised between industry and education. He is University of Wales Professor of Optics at Glyndwr University; Professorial Research Associate, University College of London and Research Director at Zeeko Ltd.

His subject was his involvement with the development of what will be the world’s largest telescope to date. Having given us a brief glimpse of the history of significant past large telescopes, and of the competitors for the present instrument, he gave his audience a very interesting insight into the construction of the telescope, including the complexities of producing the 948 hexagonal mirrors which will comprise this latest dish, which will operate from the E-ELT site in the Atacama Desert in Chile. He explained some of the logistical and technical difficulties which limit the size of one-piece mirrors and which necessitate the complex positioning and alignment of multiple mirrors to work as one in larger instruments. This will enable the telescope to probe more thoroughly into deeper space and to provide information to tackle issues such as those outlined by Mr Gilligan. Later Professor Walker alluded to the oft asked question as to why spend money on space exploration at a time of severe financial constraints. His answer was to remind us not only of the astronomical advances and of the many valuable insights which are gained but also of the enormous “spin-offs” which accompany such work, including the challenge of laser fusion which could probably meet the world’s energy requirements from seawater. And this would be an answer to a question which cannot be dodged! Other spinoffs have included the development of hi-tec polishing machines for the mirrors which have already found application in medicine and industry.

It was reassuring to hear of Britain at the forefront and the professor’s enthusiasm for his subject was infectious. His talk provided an appetiser for non-members present to join the Liverpool Astronomical Society.

This Society has many functions besides holding these monthly meetings considering engaging topics.

There are public events, held in local parks or educational establishments, and members meet weekly at Leighton Observatory at Pex Hill, on Wednesday's at 7.30 pm.

In addition members can receive publications and are entitled to telescope rental. Experts are also on hand to help those less experienced.

Membership fees are £15 pa for adults and £5 for juniors (10 to 17 years old).   For more information; click on:- liverpoolas.org.