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Iconic black-hole image gets swirly
This swirling version of the now-iconic black hole at the centre of the M87 galaxy reveals the nature of the region’s magnetic field. The image was produced by the Event Horizon Telescope (EHT) — which in 2019 produced the first-ever image of a black hole. It shows polarized light emitted by jets hurled by the black hole, accelerating along magnetic fields as they go. “The polarised light has these curved swoops like a spiral,” says astrophysicist Sara Issaoun. “This tells us that the magnetic field around the black hole is ordered, and this is really important because only an ordered magnetic field can launch jets — a scrambled magnetic field cannot do that.”
Read more: Black hole pictured for first time — in spectacular detail (Nature | 7 min read, from 2019)
Reference:The Astrophysical Journal Letters paper 1 & paper 2
3,000-year-old treasures of Sanxingdui
Archaeologists in China have unveiled more than 500 artefacts from six ‘sacrificial pits’ in Sanxingdui dating back more than 3,000 years. The site in southwestern Sichuan province provides a glimpse into an ancient civilization at the heart of what is thought to be the Shu kingdom. The findings include artistic carvings on a bean-sized piece of ivory, and fragments of a golden mask described as a “rare, dazzling treasure” by archaeologist Zhao Congcang.
How humans grow such large brains
Scientists have identified a molecular switch that controls brain growth, making human brains three times larger than those of great apes. In studies on mini-brains grown in a dish, they were able to tinker with the mechanism to make gorilla brain tissue larger and human brain tissue smaller.
Features & opinion
SARS-CoV-2 variants are converging
Evidence is growing that the SARS-CoV-2 variants that are evolving around the world share similar combinations of mutations, writes evolutionary microbiologist Vaughn Cooper. In the United States, Cooper’s laboratory has found at least seven genetically independent lineages that acquired a mutation at one particular spot on the virus’s infamous spike protein. Limiting infections will be key to reducing the virus’s opportunity to mutate in ways that make it even more dangerous. “These viral adaptations are already rewriting our biology textbooks on convergent evolution,” writes Cooper. “Let’s strive to limit new material.”
Scientific American | 6 min read
The cruel wages of lead
Hundreds of workers have been exposed to extreme amounts of lead at Florida’s lone lead smelter, which recycles car batteries. A Tampa Bay Times investigation, which is being revealed in a series of stories starting today, reveals dangerous levels of the neurotoxin and the profound consequences for workers and their families.