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CSIRO Technology behind World’s Largest Telescope

By David Reneke

CSIRO technology is behind the world’s largest single dish radio telescope, and astronomers have found a peanut-shaped galaxy.

The National Astronomical Observatories of the Chinese Academy of Sciences has teamed up with CSIRO engineers to develop the world’s largest single dish radio telescope. The 500-metre Aperture Spherical Telescope (FAST) easily dwarfs the current largest single dish telescope, the Arecibo Observatory in Puerto Rico. It will also be one of the most sensitive, capable of receiving weaker and more distant radio signals, in turn helping to explore the nature, origins and evolution of the universe.

The telescope’s 19-beam receiver is being designed and built in Australia by CSIRO engineers. “This is a really exciting project and builds on 40 years of CSIRO collaboration with Chinese industry and research organisations,” said CSIRO Chief Executive Dr Larry Marshall.

Most radio telescopes use receivers that can only access one part of sky at a time, but CSIRO scientists have designed receivers with many separate, simultaneous beams, making it practical for FAST to search a large portion of the sky for faint and hidden galaxies. “The powerful receiver we’ve created for FAST is the result of our long history developing cutting-edge astronomy technology to receive and amplify radio waves from space,” said Acting Director CSIRO Astronomy and Space Science, Dr Douglas Bock. “Extending our technology and collaboration to China and working on what will become the world’s largest radio telescope really cements our position as a global R&D leader in this space.”

This state-of-the-art instrument will help astronomers expand their understanding of the universe. FAST will make it possible for us to look for a range of extremely interesting and exotic objects, like the thousands of new pulsars in our galaxy, and perhaps other distant galaxies too.


Double Peanut Shell-Shaped Galaxy Discovered

Astronomers at Swinburne University of Technology have discovered an unusually shaped structure in two nearby disc galaxies. The distribution of stars bulging from the centre of these galaxies’ flattened discs resembles two peanut shells, with one neatly nested within the other.

“This is the first time such a phenomenon has been observed,” says Bogdan Ciambur, the PhD student who led the investigation. “We expect the galaxies’ surprising anatomy will provide us with a unique view into their pasts. Deciphering their history can tell us about transformations that galaxies like our own Milky Way might experience.”

The Swinburne team recently developed new imaging software that make it possible to find the delicate features that led to this discovery.

Using data from the Hubble Space Telescope and the Sloan Digital Sky Survey, the researchers realised that two of the galaxies they were studying – NGC 128 and NGC 2549 – displayed a peanut shell configuration at two separate layers within the three-dimensional distribution of stars within them.

“Ironically, these peanut-shaped structures are far from peanut-sized,” says Swinburne Professor Alister Graham, co-author of the research. “They consist of billions of stars typically spanning 5–25% of the length of the galaxies.”

Although the bulges of both galaxies were already known to display a single peanut shell pattern, astronomers had never before observed the fainter second structure in any galaxy.

Astronomers think peanut-shaped bulges are linked to a bar-shaped distribution of stars observed across the centre of many rotating galaxy discs. The NGC 128 and NGC 2549 galaxies contain two such bars. One way the peanut-shaped structures may arise is when these bars of stars bend above and below the galaxy’s central disc of stars.

Ciambur likens this bending to water running through a garden hose: when the water pressure is low the hose remains still, but when the pressure is high the hose starts to bend.

“By directly comparing real galaxies with state-of-the-art simulations, we hope to better understand how galaxies evolve,” says Ciambur. “The discovery is exciting because we can more fully test the growth of bars over time, including their lengths, rotation speeds and periods of instability.”

The study may also shed new light on the peanut-shaped bulge of our Milky Way galaxy, which some astronomers suspect contains two stellar bars.

The research has been published in Monthly Notices of the Royal Astronomical Society (http://tinyurl.com/zqatk7l).


David Reneke is an astronomy lecturer and teacher, a feature writer for major Australian newspapers and magazines, and a science correspondent for ABC and commercial radio. Subscribe to David’s free Astro-Space newsletter at www.davidreneke.com