ASTRO3D

Bend it like Einstein: Astronomers turn galaxies into magnifiers

New technique helps NASA’s James Webb Space Telescope

Astronomers have turned a cluster of galaxies into a gargantuan magnifying lens, using it to study another galaxy, 10.7 billion light years away, in unprecedented detail.

Taking advantage of a phenomenon known as “gravitational lensing”, the team of scientists, led by NASA Goddard Space Flight Centre scientist Dr Soniya Sharma, identified star forming regions in the distant and ancient galaxy.

The research was funded by Australia’s ARC Centre of Excellence in All Sky Astrophysics in 3 Dimensions (ASTRO 3D), and will be of direct benefit to NASA’s next orbiting observer.

Without the use of the massive magnifying effect, the galaxy, dubbed cswa128, would be a tiny blur to even the most powerful telescopes on Earth. With it, the astronomers can see stars being formed just three billion years after the Big Bang.

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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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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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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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Canberra astronomer becomes first Australian to win major US science award in 133 years

Lisa Kewley has transformed our understanding of the early years of the Universe, the development of galaxies, and what happens when they collide.  

2020 James Craig Watson medal winner Professor Lisa Kewley in her office. Credit: ASTRO 3D

For her pioneering investigations across theory, modelling and observation, she will receive the US National Academy of Science’s biennial James Craig Watson Medal in Washington DC.

“At school I thought physics would be too hard.  But I had a wonderful physics teacher whose love for astronomy was contagious!” says Lisa.

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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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