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.
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?
Day and night at the Anglo Australian Telescope. Half right image taken in the late afternoon, the Moon is up. Half left image taken just some few minutes before the beginning of the morning twilight of the same night. Orion and the Pleiades shine over the AAT on a very dark night. 4-5 November 2011. Siding Spring Observatory, NSW, Australia. Credit: Dr Ángel R. López-Sánchez/Australian Astronomical Optics/Macquarie University/ASTRO 3D
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.
Australian researchers find ways to overcome the blinding glare of quasars
NASA’s James Webb Space Telescope will uncover galaxies never before seen by humanity, Australian-led research reveals.
The telescope, due to launch in late 2021, is the largest, most powerful and complex space telescope ever built.
Two new studies led by Madeline Marshall from Australia’s University of Melbourne and the ARC Centre of Excellence in All Sky Astrophysics in 3 Dimensions (ASTRO 3D) find that the Webb will be able to reveal galaxies currently masked by powerful lights called quasars.
Unusual galaxy set to prompt rethink on how structures in the Universe form
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 journalNature Astronomy, is set to shake up theories about the earliest formation of galactic structures and how they evolve.
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.
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.
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.
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.
