ASTRO 3D

Astronomers see ‘cosmic ring of fire’, 11 billion years ago

Unusual galaxy set to prompt rethink on how structures in the Universe form

Full paper, Full video, and images available. Details below.

Astronomers have captured an image of a super-rare type of galaxy – described as a “cosmic ring of fire” – as it existed 11 billion years ago.

The galaxy, which has roughly the mass of the Milky Way, is circular with a hole in the middle, rather like a titanic doughnut. Its discovery, announced in the journal Nature Astronomy, is set to shake up theories about the earliest formation of galactic structures and how they evolve.

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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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Star-quake vibrations lead to new estimate for Milky Way age

Data gathered by NASA’s now defunct Kepler telescope provides a solution to an astronomical mystery.

An artist impression of the Milky Way, showing the thick and thin discs.
Credit: NASA/JPL Caltech/R.Hurt/SSC

Star-quakes recorded by NASA’s Kepler space telescope have helped answer a long-standing question about the age of the “thick disc” of the Milky Way.

In a paper published in the journal Monthly Notices of the Royal Astronomical Society, a team of 38 scientists led by researchers from Australia’s ARC Centre of Excellence for All Sky Astrophysics in Three Dimensions (ASTRO-3D) use data from the now-defunct probe to calculate that the disc is about 10 billion years old.

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Not long ago, the centre of the Milky Way exploded

Researchers find evidence of a cataclysmic flare that punched so far out of the Galaxy its impact was felt 200,000 light years away.

An artist’s impression of the massive bursts of ionising radiation exploding from the centre of the Milky Way and impacting the Magellanic Stream.
Credit: James Josephides/ASTRO 3D

A titanic, expanding beam of energy sprang from close to the supermassive black hole in the centre of the Milky Way just 3.5 million years ago, sending a cone-shaped burst of radiation through both poles of the Galaxy and out into deep space.

That’s the finding arising from research conducted by a team of scientists led by Professor Joss Bland-Hawthorn from Australia’s ARC Centre of Excellence for All Sky Astrophysics in 3 Dimensions (ASTRO 3D) and soon to be published in The Astrophysical Journal.

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And then there was light: looking for the first stars in the Universe

Researchers hunt for a 12-billion-year-old signal that marks the end of the post Big Bang “dark age”.

In this image of the Epoch of Reionisation, neutral hydrogen, in red, is gradually ionizsed by the first stars, shown in white.Credit: Paul Geil and Simon Mutch

Astronomers are closing in on a signal that has been travelling across the Universe for 12 billion years, bringing them nearer to understanding the life and death of the very earliest stars.

In a paper on the preprint site arXiv and soon to be published in the Astrophysical Journal, a team led by Dr Nichole Barry from Australia’s University of Melbourne and the ARC Centre of Excellence for All Sky Astrophysics in 3 Dimensions (ASTRO 3D) reports a 10-fold improvement on data gathered by the Murchison Widefield Array (MWA) – a collection of 4096 dipole antennas set in the remote hinterland of Western Australia.

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Anaemic star carries the mark of its ancient ancestor

Australian-led astronomers find the most iron-poor star in the Galaxy, hinting at the nature of the first stars in the Universe.

A visualisation of the formation of the first stars. Credit: Wise, Abel, Kaehler (KIPAC/SLAC)

A newly discovered ancient star containing a record-low amount of iron carries evidence of a class of even older stars, long hypothesised but assumed to have vanished.

In a paper published in the journal Monthly Notices of the Royal Astronomical Society: Letters, researchers led by Dr Thomas Nordlander of the ARC Centre of Excellence for All Sky Astrophysics in 3 Dimensions (ASTRO 3D) confirm the existence of an ultra-metal-poor red giant star, located in the halo of the Milky Way, on the other side of the Galaxy about 35,000 light-years from Earth.

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