Tag Archives: International Centre for Radio Astronomy Research (ICRAR)

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

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 journal Nature Astronomy, is set to shake up theories about the earliest formation of galactic structures and how they evolve.

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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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