Sky survey provides clues to how they change over time.
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.
An international team of researchers led out of Macquarie University has demonstrated a new approach for converting ordinary laser light into genuine quantum light.
Their approach uses nanometre-thick films made of gallium arsenide, which is a semiconductor material widely used in solar cells. They sandwich the thin films between two mirrors to manipulate the incoming photons.
The photons interact with electron-hole pairs in the semiconductor, forming new chimeric particles called polaritons that carry properties from both the photons and the electron-hole pairs. The polaritons decay after a few picoseconds, and the photons they release exhibit distinct quantum signatures.
The teams’ research was published overnight in the journal Nature Materials.
An Aussie eucalypt can ‘remember’ past exposure to extreme heat, which makes the tree and its offspring better able to cope with future heatwaves, according to new research from Macquarie University.
This finding could have important implications for restoring ecosystems and climate-proofing forestry, as the number of hot days and heatwaves increase due to climate change.
“Unlike animals, which can bury deeper into the soil or flee to cooler locations, plants are stuck in one spot and so must be able to withstand extreme conditions in situ,” says Dr Rachael Gallagher, senior author of the paper published in the journal Functional Ecology.
New Australian technology will enable real-time monitoring of wine throughout its fermentation and maturation process, reducing spoilage and improving quality.
The “Smart Bung” technology has been pioneered at the University of Adelaide by the Institute for Photonics & Advanced Sensing (IPAS) and the School of Agriculture, Food and Wine (SAFW). The work is led by Prof Tanya Monro, Director of IPAS.
An optical fibre sensor incorporated into the bung of a wine cask can detect substances that might cause the wine to spoil. The optical fibres have tiny holes that take up minute samples of the wine. The sensor shines light through the fibres to determine the concentration of certain important chemicals, such as hydrogen peroxide and sulphur dioxide—all without having to open the cask. The system will enable continuous, real-time cask-by-cask monitoring and an immediate response if problems are detected.