What the scientists are saying…

Alien space rock spotted For the first time ever, an interstellar asteroid – from another solar system – has been observed crossing into our system. The rocky intruder, which measures around 400m across, was detected in mid-october by a team in Hawaii. “It didn’t move like comets or asteroids normally do,” said Rob Weryk, of the University of Hawaii. The asteroids from our own solar system orbit the Sun elliptically. By contrast, this one was found to be on a hyperbolic trajectory. It skirted the Sun in early September, before passing Earth at a distance of 15 million miles, and is now racing away from us, at a speed of about 15 miles per second, getting fainter and fainter all the time – which is frustrating for astronomers who had long anticipated such an event. The gravitational pull of our gas giants, like Jupiter, catapulted trillions of comets and asteroids from the early solar system into interstellar space. The presumption was that the planets in other solar systems had done the same, littering space with objects that might, one day, come our way. “We have waited a long time [for this],” said planetary scientist Dr Alan Stern of the Southwest Research Institute in Boulder, Colorado.

Blood test for miscarriages A blood test designed to detect whether pregnant women are at high risk of miscarriage has achieved impressive results in its first clinical trials, reports The Times. The test, developed by a team in San Francisco, screens for molecules called microrna, which are found in blood cells in the placental bed. Their presence is thought to indicate problems with blood supply, which can trigger a range of complications. In four trials, involving a total of 160 births, the test achieved 92% accuracy for predicting both miscarriages and “late premature” births (those occurring between 32 and 37 weeks). For “extremely premature” births, accuracy was 98% .The test was also 82% accurate in spotting pre-eclampsia. The researchers believe that these complications are all related to the supply of blood to the foetus, and that potential treatments could include blood-thinning drugs such as heparin. However, the research is in its early days and larger trials are needed.

Do microplastics taste good? Corals appear to enjoy the taste of plastic – raising further fears about the threat to marine life posed by pollution. Most of the sea creatures that ingest microplastics – tiny fragments measuring less than 5mm in diameter – probably do so because they mistake them for prey. Corals, however, are blind, suggesting a different motivation. To cast light on this, scientists at Duke University in North Carolina ran a two-part lab experiment: first, they offered corals eight types of plastic and similarly sized particles of sand. Next, they exposed the corals to a choice of clean plastics or ones coated in nutritious microbes, which corals are presumed to like. In the first experiment, the corals gobbled up the plastics while rejecting the sand; in the second, they still preferred the clean plastics by a threefold margin – suggesting that the plastic itself “contains something that makes it tasty”. That corals are eating plastic is alarming, because it can get stuck in their tiny guts; however, the team hopes that if they can identify what chemical in plastic gives it its flavour, manufacturers might be persuaded to remove it.

Aspirin may ward off cancers The largest-ever study into the link between aspirin and cancer has suggested that sustained use of the drug can reduce the risk of several forms of the disease, says The Daily Telegraph. Researchers at The Chinese University of Hong Kong, who tracked more than 600,000 people, found that long-term aspirin use – that is, taking it in low doses every day for an average of seven years – was associated with a 47% reduction in the risk of liver or oesophagal cancer, a 38% reduction in the risk of gastric cancer and a 34% reduced risk of pancreatic cancer. Professor Kelvin Tsoi, the lead researcher, noted that the positive effect was most marked on cancers within the digestive tract; aspirin had no effect on a range of other cancers, including breast, bladder and kidney. Taking aspirin has in the past been linked with a reduced risk of heart attacks and strokes. However, prolonged use is associated with bleeding of the gut, and people should talk to their GPS before taking it daily.