astronomy

At cosmic noon, puffy galaxies make stars for longer

Galaxies with extended disks maintain productivity, research reveals

Massive galaxies with extra-large extended “puffy” disks produced stars for longer than their more compact cousins, new modelling reveals.

In a paper published in the Astrophysical Journal, researchers led by Dr Anshu Gupta and Associate Professor Kim-Vy Tran from Australia’s ARC Centre of Excellence in All Sky Astrophysics in 3 Dimensions (ASTRO 3D), show that the sheer size of a galaxy influences when it stops making new stars. 

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The secrets of 3000 galaxies laid bare

Completion of Australian-led astronomy project sheds light on the evolution of the Universe

The complex mechanics determining how galaxies spin, grow, cluster and die have been revealed following the release of all the data gathered during a massive seven-year Australian-led astronomy research project.

The scientists observed 13 galaxies at a time, building to a total of 3068, using a custom-built instrument called the Sydney-AAO Multi-Object Integral-Field Spectrograph (SAMI), connected to the 4-metre Anglo-Australian Telescope (AAT) at Siding Spring Observatory in New South Wales. The telescope is operated by the Australian National University.

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Free telescopes set school kids dancing with the STARS

Astronomers head to the country to spark student interest in what lies above.

ANU astronomer Brad Tucker showing students from Rockhampton High School how to use their powerful new telescope. Credit: ANU Media

Children in remote and regional schools will soon be visited by astronomers bearing gifts in a quest to kindle interest in the cosmos.

The scientists – drawn from the ranks of the ARC Centre of Excellence for All Sky Astrophysics in 3D (ASTRO 3D) and the Australian National University – will donate a powerful telescope and high-tech accessories to each school so classes can continue to explore the Universe long after the astronomers have left.

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Orbits of ancient stars prompt rethink on Milky Way evolution

Australian telescopes and European satellite combine to reveal unexpected motions among the Galaxy’s rarest objects

Theories on how the Milky Way formed are set to be rewritten following discoveries about the behaviour of some of its oldest stars.

An investigation into the orbits of the Galaxy’s metal-poor stars – assumed to be among the most ancient in existence – has found that some of them travel in previously unpredicted patterns.

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Playing detective on a galactic scale: huge new dataset will solve multiple Milky Way mysteries

Australian-led GALAH project releases chemical information for 600,000 stars.

How do stars destroy lithium? Was a drastic change in the shape of the Milky Way caused by the sudden arrival of millions of stellar stowaways?

These are just a couple of the astronomical questions likely to be answered following the release today of ‘GALAH DR3’, the largest set of stellar chemical data ever compiled.

The data, comprising more than 500 GB of information gleaned from more than 30 million individual measurements, was gathered by astronomers including Sven Buder, Sarah Martell and Sanjib Sharma from Australia’s ARC Centre of Excellence in All Sky Astrophysics in 3 Dimensions (ASTRO 3D) using the Anglo Australian Telescope (AAT) at the Australian Astronomical Observatory at Siding Spring in rural New South Wales.

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Can you see the stars?

Who has the darkest skies?

Tell us what you can see on the longest night, help us map Australia’s light pollution, and set a world record

Stunning video overlay and photos, spokespeople in all States and Territories

Stargazing at Siding Spring Observatory, near Coonabarabran, NSW.
Credit: Angel Lopez-Sanchez

Scientists are asking all Australians to step outside on the longest night of the year to help them measure light pollution around the country.

“We’re expecting thousands of people to join us on Australia’s longest night, Sunday 21 June, to help researchers create a map of Australia’s darkest skies, and learn about light pollution and its effect on people, animals, and astronomy,” says Marnie Ogg, CEO and founder of the Australasian Dark Sky Alliance.

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Hungry galaxies grow fat on the flesh of their neighbours

Full paper available here, read on for media release, photos, captions and background information.

Modelling shows big galaxies get bigger by merging with smaller ones

Distribution of dark matter density overlayed with the gas density. This image cleanly shows the gas channels connecting the central galaxy with its neighbours. Credit: Gupta et al/ASTRO 3D/ IllustrisTNG collaboration.

Galaxies grow large by eating their smaller neighbours, new research reveals.

Exactly how massive galaxies attain their size is poorly understood, not least because they swell over billions of years. But now a combination of observation and modelling from researchers led by Dr Anshu Gupta from Australia’s ARC Centre of Excellence for All Sky Astrophysics in 3 Dimensions (ASTRO 3D) has provided a vital clue.

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Hire more LGBTQ and disabled astronomers or risk falling behind, review finds

Analysis finds gender equity among star scientists improving, but big challenges remain.

Professor Lisa Kewley, director of the ARC Centre of Excellence in All Sky Astrophysics (ASTRO 3D), in front of Australia’s Reynolds telescope, which dates from 1927.
Credit: ASTRO 3D

Ensuring research opportunities for indigenous, disabled and LGBTQ astronomers is essential if Australian research is to succeed in the new era of “mega-telescopes”, a major analysis has found.

In a paper published in the journal Nature Astronomy, Professor Lisa Kewley, director of the ARC Centre of Excellence in All Sky Astrophysics (ASTRO 3D), finds that encouraging astronomers from marginalised communities will increase the chances of significant research discoveries.

“Studies show that increased diversity up to the highest levels of organisations, and effective diversity management, leads to organisations outperforming their competition in innovation, productivity and profit because more ideas are produced,” she says.  

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Spin doctors: Astrophysicists find when galaxies rotate, size matters

Sky survey provides clues to how they change over time.

A simulation showing a section of the Universe at its broadest scale. A web of cosmic filaments forms a lattice of matter, enclosing vast voids. Credit: Tiamat simulation, Greg Poole

The direction in which a galaxy spins depends on its mass, researchers have found.

A team of astrophysicists analysed 1418 galaxies and found that small ones are likely to spin on a different axis to large ones. The rotation was measured in relation to each galaxy’s closest “cosmic filament” – the largest structures in the universe.

Filaments are massive thread-like formations, comprising huge amounts of matter – including galaxies, gas and, modelling implies, dark matter. They can be 500 million light years long but just 20 million light years wide. At their largest scale, the filaments divide the universe into a vast gravitationally linked lattice interspersed with enormous dark matter voids.

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