Reaching for the stars
If you dream of being an astrophysicist then working in retail as a computer operator and salesman is probably not going to be exactly what you want.
University of Leicester astrophysicist Nigel Bannister had been doing just that for seven years, becoming more and more desperate in his wish to study astronomy. At school he had – in his words – “suffered from a typical teenage malaise and flunked completely.” So when he finally made the decision to pursue his interest he took a crash A Level course and came to Leicester as a mature student.
IN THE BLUE RIDGE MOUNTAINS OF
VIRGINIA: Nigel Bannister, from the University's Space Research
Centre, taking a break in Virginia's Shenandoah National Park during a
visit to Washington DC to work at the US Naval Research Laboratory.
He chose Leicester because the university had been recommended by a couple of space scientists he knew. “Leicester had a record of not just looking through telescopes, but building equipment. The University was among the big players in space research. Also I like the city, with its green environmental policies.”
That was all back in 1993.and two degrees later he is at the University’s Space Research Centre with Dr Martin Barstow investigating – among other things – white dwarf stars.
He explained: “These are stars like our Sun at the point when they run out of fuel. The Sun is about 4.5 billion years old and for most of that time it has been turning hydrogen to helium. But it will run out of that gas and undergo changes to its structure. Most of the gas will blow away, leaving a hot dense and very small core. At that point it will be the size of Earth, but with a mass comparable to that of the Sun. Then it will fade away. Ninety-five per cent of stars will become white dwarfs.”
Using spectroscopy to split up the star light, white dwarfs can become laboratories providing conditions more extreme than on Earth. Fraunhofer Lines, a series of lines in a spectrum, give indicators of chemicals in the star, and brightness graphs show the stage the white dwarf has reached. “You can go further and further back in the life of the galaxy,” Nigel said, “but the information ends quite abruptly. There hasn’t been enough time in the life of the galaxy for the white dwarfs to cool down enough to change colour beyond a certain point.”
While studying for a PhD with Martin Barstow, they developed instrumentation to study white dwarfs and sent the equipment up into space. Nigel admitted: “That was a great feeling, standing in the desert in New Mexico while two miles away they send up something you have been building. It’s awe-inspiring.”
The rocket was only designed to be in space for 5-10 minutes but it provided answers to questions of technology to be used in future permanent space missions.
Nigel Bannister from the University's Space Research Centre, in New
Mexico for the launch of a rocket carrying instrumentation developed
While Nigel is still involved in that project, he also is now working with Professor George Fraser at the University of Leicester, designing the “Lobster-ISS” X-ray telescope which will fly on the International Space Station.
He explained again: “You are looking at an X-ray sky. Every 90 minutes you cover the entire sky, and Lobster can see everything. This makes a big difference when trying to study unpredictable events. After all, you wouldn’t try to photograph lightning by pointing your camera at one small piece of the sky and just hoping - but that is how we have to use most space telescopes at present. Lobster can tell us where we should be looking, and then we can train other telescopes on that point. It’s a big step forwards.”
The Leicester-led project involving the International Space Station on which Nigel is working has been well-received so far by the European Space Agency, and Nigel feels it has an exciting future as a high profile space station mission that may lead to some dramatic discoveries. It involves collaboration with international groups of space scientists, all with expertise in different types of phenomena.
Nigel Bannister is just as passionate about astrophysics as he was when it was just a dream during his retail days. “We shouldn’t apologise for space research. One of the things that separates us from the animal world is the urge to expand our horizons, just as Magellan and other explorers did centuries ago.
“There have always been people who said : ‘Why go to other lands when you could spend the money on starving people here’. But I think it’s part of the process of knowing who we are. It’s important in its own right, but there are also medical spin-offs – as in the work of John Lees’ BioImaging Unit here at the University of Leicester. You rarely know where the next key development may come from in any field.”
Nigel Bannister, Research Assistant, University of Leicester Space Research Centre, can be contacted by telephone 0116 252 1043, email