Astronomers have studied the Sun for as long as the concept of observation has existed. Indeed, the star at the heart of our solar system has played an important role in helping us to understand the universe on the grandest scales. Detailed and precise observations of the Sun have, for example, constrained our ideas on how other stars evolve, while our ability to pin down the age of stars has been an important plank in the attempts to describe the origins and evolution of the universe.
Enormous advances in solar and stellar physics have been made in recent years as a result of helioseismology – the study of vibrations on the surface of the Sun. However, the Sun is only one star among many. While we believe it is a typical star, we do not know for certain. What we need are observations of the oscillations in other solar-like objects. Sadly such studies are difficult because all other stars are far away and the oscillations are very small. Now Tim Bedding of the University of Sydney and co-workers in Australia, the US, Denmark and Switzerland have announced the detection of solar-like oscillations on Beta Hydri – a star much like our Sun, except that it is older and more evolved (T Bedding et al. 2001 Astrophys. J. 549 L105). Although other groups had previously claimed to have detected oscillations on other Sun-like stars, most solar and stellar seismologists felt that these results were not robust.
In the June issue of Physics World, Yvonne Elsworth of the University of Birmingham, UK, discusses why the results of Bedding and co-workers, in contrast, look very promising.
