Space shuttle Atlantis blasts off on space station supply run guardian.co.uk

Britain's aspirations to become a spacefaring nation inched a little closer tonight as thousands of microscopic worms boarded the Atlantis space shuttle at Cape Canaveral for a mission to the international space station.

The diminutive space travellers are being flown into orbit as part of research that scientists hope will help explain how astronauts build and lose muscle as they circle the Earth.

The test subjects, from a rubbish tip in Bristol, will be studied in the weightless confines of the Japanese Kibo laboratory, one of the most recent additions to the $100bn space station. Predecessors of the latest batch of worms made news in 2003 when they survived the Columbia space shuttle disaster. They were discovered in a protective container several weeks after the craft was destroyed during re-entry.

Dr Nathaniel Szewczyk, a scientist at the University of Nottingham who has worked on three previous missions, said the nematode worms will be used to study biological signals that make muscle proteins degrade. He said the worms are the perfect substitute for examining the long-term effects of weightlessness on humans.

"We can learn things in space that we would not be able to learn on Earth," Szewczyk said. "If we can identify what causes the body to react in certain ways in space we establish new pathways for research back on Earth."

The worms have been carefully selected for the mission and will be exposed to conditions in space for four days and then frozen in preparation for the return journey. The effect of this journey on their muscle mass will be investigated once the worms are returned to the university's laboratories.