Over aeons of time cosmic gas comes together, stars begin to form, supernovae explode, galaxies collide. And computational astronomers can watch it all unfold inside a supercomputer. That’s the kind of work post-doctoral fellows Rob Crain and Greg Poole are doing at the Swinburne Centre for Astrophysics and Supercomputing. Continue reading Supercomputers bring theory to life
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Recording the impact of a super-massive black hole
At the centre of a nearby galaxy lurks an object of huge interest, a super-massive black hole. CSIRO scientists have used their radio telescopes to take a picture of the galaxy surrounding it, a task some thought could not be done, because of the sheer size and radio brightness of the scene. The image of Centaurus A took about 1,200 hours of observations and a further 10,000 hours of computer processing to put together, but the work is already beginning to bear fruit.
“We didn’t generate this image just to make a pretty picture,” says lead scientist Ilana Feain of CSIRO Astronomy and Space Science. “We want to understand in detail how the energy from super-massive black holes influences the formation and evolution of their host galaxies.” Continue reading Recording the impact of a super-massive black hole
Japanese spacecraft calls Australia home
On 13 June 2010, a Japanese spacecraft bearing pieces of another world parachuted down to Australian soil after a seven-year-long journey through deep space.
During its journey, the spacecraft, called Hayabusa, encountered the 530-metre-long asteroid called Itokawa in November 2005, and briefly landed on it. The Japanese Aerospace Exploration Agency (JAXA) designed Hayabusa to collect samples of the asteroid’s surface. Hayabusa then landed at the Department of Defence’s remote Woomera Prohibited Area in the South Australian desert. Fifty years ago, Woomera was one of the most active rocket launch sites in the world. It is still the largest land-based test range on the planet. Continue reading Japanese spacecraft calls Australia home
Bringing undiscovered Earths into focus
How many of the planets scattered across the Universe have the potential to harbour life? An observatory being built in Tasmania is poised to help answer just that question.
Astronomers at the University of Tasmania (UTas) currently use the Mount Canopus Observatory in Hobart to search for Earth-like planets orbiting distant suns—but the growing city is compromising the observatory’s view of space. “Light is driving us away,” says John Greenhill, the Observatory’s director. Continue reading Bringing undiscovered Earths into focus
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.
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.
Continue reading Doubling up pays dividends in exoplanet hunt
Stellar immigration
If the Milky Way did grow by swallowing up smaller galaxies, then another team suspects it knows where in the Milky Way some of those alien stars are hiding.
Duncan Forbes of Swinburne University of Technology and his Canadian colleague Terry Bridges are using Hubble Space Telescope data to identify clusters of alien stars, using the fact that their age and chemical composition differs from their neighbours.
Profiling and fingerprinting the stars
This story continues from Galactic archaeology— digging into the Milky Way’s past
But already, another Australian-led innovation in astronomical instrumentation is providing researchers with the critical information they need to understand the motions of stars within different parts of our galaxy, such as its main body, the bulging core, and the extended halo that surrounds it. Researchers are also searching for evidence of galactic cannibalism—swarms of stars that could be remnants of dwarf galaxies consumed by the Milky Way.
The innovation, called the 6dF instrument, is being used by a multinational consortium, the RAdial Velocity Experiment (RAVE), to measure the radial velocities of more than half a million stars. It is mounted on the Australian National University’s UK Schmidt Telescope at Siding Spring in New South Wales. Radial velocity is movement toward or away from the observer along the light of sight, as distinct from motion across the line of sight. The survey, which began in 2003, will be completed in 2011. Continue reading Profiling and fingerprinting the stars
Galactic archaeology— digging into the Milky Way’s past
Ken Freeman is hunting for fossils. But he’s not looking for old bones—he’s exploring the very origin and history of our Milky Way galaxy.
Conventional theory says that our galaxy grew big by engulfing smaller ones. If this is correct, stars from the original galaxies should be still identifiable within the main mass of stars via several tell-tale signs, from unusual velocities to spectral types. These stellar fossils would point to the galaxy’s birth and growth. Continue reading Galactic archaeology— digging into the Milky Way’s past
Nurturing super astronomers at home
Advanced telescopes need advanced astronomers to run them. Australia is matching the millions of dollars it is investing in new telescope technology with funds to help train the rising stars of Australian astronomy.
“We’ve had big investments in infrastructure, and now we need young scientists with the expertise to use them,” says Elaine Sadler, professor of Astrophysics at the University of Sydney and chair of the National Committee for Astronomy.
One new tranche of research funding for early career astronomers comes in the form of three-year Super Science Fellowships from the Commonwealth Government. In 2011, 14 young astronomers became Super Science Fellows, joining the 17 who started work in 2010. All up, astronomy will receive one-third of the Federal Government’s $27 million commitment to the Fellowships program. Continue reading Nurturing super astronomers at home
The destruction of a star
You have to be well prepared, quick and lucky to take a picture of an explosion, especially if that explosion occurred 11 billion years ago in a remote part of the Universe. Having the right equipment, plus friends in high places, certainly helps. And that’s exactly what the Zadko Telescope—managed by the University of Western Australia at the Gingin Observatory about 70 kilometres north of Perth—does have.
In December 2008, just after it was installed, the telescope was first on the scene to record for future analysis the afterglow of a momentous event—a huge explosion as a star collapsed into a black hole releasing a massive gamma-ray burst. It’s the kind of happening the one-metre Zadko Telescope, currently the largest optical telescope in Western Australia, was built to observe. And it performed flawlessly, outpacing the world’s most powerful telescopes at the European Southern Observatory in Chile.