Collision course on an intergalactic highway
Astronomers have created the clearest images ever of a galaxy cluster with a black hole at its heart, speeding along an intergalactic highway of matter – on a collision course with two much larger galaxy clusters.
Scientists have long theorised that streams of gas connect clusters of galaxies across the universe, but this gas is so thin that it has eluded detectors until recently. In 2020, an intergalactic thread of gas was discovered stretching out more than 50 million light-years across the Universe, confirming the theory.
Now astronomers have imaged a galaxy cluster moving along this thread, with jets of matter streaming out behind it.
The observation, announced in a press conference last week, was a team effort between telescopes across the world and in space, including CSIRO’s ASKAP radio telescope in Australia.
Co-author Andrew Hopkins from Macquarie University explains: “The excellent sensitivity of the ASKAP telescope to faint extended radio emission is the key that allows the detection of these jets of radio emission from the supermassive black hole. The shape and orientation of these jets in turn provide important clues to the motion of the galaxy hosting the black hole.”
Australian mouse resurrected from extinction
For over 160 years, scientists have thought that Gould’s mouse (Pseudomys gouldii) was extinct. This native rodent was once found in NSW and Victoria – but genomics studies involving museum specimens have just revealed that the mouse has been living on the other side of the country this whole time.
It was found to be genetically indistinguishable to another native mouse that survives on an island in Shark Bay, WA.
“It’s very exciting,” says ANU researcher Emily Roycroft, who led the study published in PNAS. “I think everybody likes the idea of removing a species from the ever-growing list of extinct species in Australia.”
The Malgana people of Shark Bay call the mouse Djoongar, and so it will now be known as the Djoongari or Shark Bay Mouse, but will keep the original scientific name.
Grape growers slow the sugar rush
New research from the University of Adelaide has found that it’s possible to increase the flavour of Cabernet Sauvignon grapes by slowing down the ripening process.
This is timely research, given that climate change is accelerating the ripening of grapes in warm and dry areas like Australia.
According to lead researcher Pietro Previtali, this leads to faster sugar accumulation in grapes, which can result in poorer colour and aroma.
“Growers therefore have to compromise between harvesting when sugar is ready but the desired flavours are missing, and prolonging grape maturation until an optimal composition of colour, mouthfeel and aroma compounds is achieved,” he says – but the latter can result in shrivelling and higher-alcohol wines.
The study, published in the Journal of Agricultural and Food Chemistry, found that ripening can be slowed through strategies such as thinning drops and irrigating later in the growing season.
Fool’s gold has real gold in it
Pyrite (iron sulphide, or FeS2) is often derided as fool’s gold, because it looks like the much more valuable metal. (The Cosmos staff think pyrite is perfectly interesting and valuable on its own.)
But researchers from Curtin University, alongside colleagues from China University of Geoscience, have found real gold (Au) atoms within pyrite.
“Previously gold extractors have been able to find gold in pyrite either as nanoparticles or as a pyrite-gold alloy, but what we have discovered is that gold can also be hosted in nanoscale crystal defects, representing a new kind of “invisible” gold,” says Denis Fougerouse, a researcher at Curtin University and first author on a paper describing the research, published in Geology.
“The more deformed the crystal is, the more gold there is locked up in defects. The gold is hosted in nanoscale defects called dislocations – one hundred thousand times smaller than the width of a human hair – so a special technique called atom probe tomography is needed to observe it.”
What cheers up vets?
A study by the University of Adelaide has surveyed 273 veterinarians to find out what makes them happy about their work.
“At a time in Australia when there are national shortages of vets, particularly in regional areas, and increased publicity about the risks and challenges in the profession, it’s important to focus on what can be done to retain those in the profession and attract more people to the field,” says Madeleine Clise, a psychologist at Adelaide and lead author on a paper describing the research, published in Vet Record.
“By focusing on what contributes to vets experiencing positive emotions, we can better understand how to improve wellbeing of those who care for our beloved pets, livestock and wildlife.”
The researchers found a range of things that cheered vets up, but interestingly, “positive relationships between clients and vets, and vets and their colleagues, was a more frequent response than positive relationships with animals.
“Vets, just like all of us, feel good when they are shown trust and respect. And a simple ‘thank you’ goes a long way,” says Clise.