7 March 2003
For immediate release
Attention: Science Writers
Unlocking the mysteries of heliumSwinburne astronomy researchers Professor Brad Gibson and Dr Chris Flynn, in collaboration with Finnish and American counterparts, have made the first accurate measurement of the rate of helium in the universe.
Despite the fact that helium exists throughout most of the universe, it has been virtually impossible to detect with any telescope. But identifying the production rate of helium is fundamental to setting the 'clock' that allows astronomers to age-date stars, galaxies and the universe itself.
The researchers, who used data from the European Space Agency's Hipparcos satellite, found that since the universe was formed billions of years ago, stars have produced almost double as much helium as other chemicals. For every kilogram of steel or sand, also formed from helium and hydrogen, stars have actually created two kilograms of helium.
Using computer calculations, the researchers predicted how brightly certain stars should shine, depending on how much hydrogen, helium and other heavier elements they contain. By comparing the production rate of helium to hydrogen, they also calculated an estimated age and life span of these stars.
Professor Gibson said:
"There are many mysteries in astronomy, but it is safe to say that we can finally put a tick mark beside one of the longer, perplexing mysteries!
"Australian researchers have played a fundamental role in demonstrating that we are not only the stuff of stars, as proclaimed by the late Carl Sagan, but also the importance of stars as helium 'factories'," said Professor Gibson.
This research was published in the 7 March issue of international journal Science.
