Doubling up pays dividends in exoplanet hunt

“Twice the resolution and all the photons,” is Prof Chris Tinney’s new catchphrase. It refers to new equipment being commissioned on the Anglo-Australian Telescope to hunt for planets beyond our Solar System (exoplanets). Chris, from the University of New South Wales, is a leader of the Anglo-Australian Planet Search (AAPS), which has found 32 exoplanets, almost 10% of the worldwide total, since 1998.

Artist’s impression of an exoplanet with moons, orbiting the star HD70642 (photo credit: David A. Hardy, astroart.org (c) PPARC)

A Doppler shift in a star’s light spectrum often indicates the presence of planets. Unlike previous equipment, which frequently missed some of that light, the new system uses a cluster of optical fibres to gather all the starlight, boosting efficiency and doubling the Doppler precision.

And a new type of intensive observation campaign also is paying dividends. AAPS has recently had two 48-night blocks of contiguous observing time, which has helped them find two small exoplanets.

“Our main aim is to find Solar System analogues,” says Chris, “ones that have a Jupiter-like planet in a middle-distance orbit, which could be indicative of having Earth-like planets in closer orbits.”

“That requires getting very high precision measurements over orbital periods the same as Jupiter (12 years) or more. We have that precision now.”

Exoplanet research is a hot-button field, and AAPS is right up there with the best of them. “Our program is bigger now than it ever was,” says Chris, “and I’m quietly confident that our new equipment will help us to remain competitive in this game.”

For more information:

The University of New South Wales
Chris Tinney
Tel: +61 (2) 9385 5168
Email: cgt@phys.unsw.edu.au
Web: www.phys.unsw.edu.au/~cgt/cgt/Homepage.html