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A visualization of a collision between two differently sized black holes.Credit: N. Fischer, H. Pfeiffer, A. Buonanno (Max Planck Institute for Gravitational Physics), Simulating eXtreme Spacetimes (SXS) Collaboration
Mismatched black-hole collision boggles
Gravitational-wave astronomers witnessed a merger between black holes of two greatly different sizes, one nearly four times more massive than the other. The unprecedented observation gave them insight into how one of the black holes spins, which had eluded them in previous gravitational-wave experiments examining mergers of equally sized black holes. The new data promise new ways to test Einstein’s general theory of relativity. “It’s an exceptional event,” said astrophysicist Maya Fishbach.
Reference: arXiv preprint
Quantum-computing pioneer quits Google
John Martinis, the physicist who spearheaded Google’s quantum-supremacy breakthrough last October, has left the company after being reassigned to an advisory role. Martinis joined Google in 2014 and brought some of his laboratory members from the University of California, Santa Barbara, where he retained an academic position. He will return to full-time academia. “Since my professional goal is for someone to build a quantum computer, I think my resignation is the best course of action for everyone,” says Martinis.
COVID-19 coronavirus outbreak
Epidemiologist Anders Tegnell (centre).Credit: Jonathan Nackstrand/AFP/Getty
Top epidemiologist explains Sweden’s unorthodox strategy
Sweden has stood almost alone in Europe in avoiding a lockdown, and in relying on voluntary, trust-based measures to stem the spread of COVID-19. “As a society, we are more into nudging,” says Anders Tegnell, the epidemiologist behind the controversial strategy. He argues that closing borders is pointless when the disease is already everywhere, and shutting schools has little effect unless it’s done very early in an outbreak. In general, Tegnell is happy with the approach, although he regrets how older people in care homes were not sufficiently protected. (Nature | 6 min read)
The coronavirus's deadly march through the body
Although the lungs are ground zero for damage caused by COVID-19, in some people the disease can devastate the heart and blood vessels, kidneys, gut,and brain — and much of its effects remain poorly understood. Science steps through the disease’s destructive path from infection onwards, with a handy infographic. (Science | 14 min read)
Pandemic brings forward UAE Mars mission
The Arab world’s first Mars mission — a spacecraft called Hope — will ship from the United Arab Emirates (UAE) to Japan weeks earlier than planned, as a result of travel restrictions imposed by the COVID-19 pandemic. “We had to expedite activities in Dubai and basically focus only on the critical testing,” project leader Omran Sharaf. Built by UAE and US engineers, the orbiter is scheduled to launch from Japan during a period that starts on 15 July, in which Earth and Mars are suitably aligned. (Nature | Continuously updated)
Experts look back on when everything seemed fine
Even some experienced infectious-disease experts did not fully appreciate how serious the COVID-19 outbreak would become. Some thought that the virus would be successfully contained in China, others were cautious about overreacting and some just couldn’t believe it could happen to them. “Everybody was in denial of this coming, including the U.S. And everybody got hit — just as simple as that,” says leading Canadian infectious-disease researcher Gary Kobinger.
Read the latest coronavirus news, continuously updated on Nature.
Read Nature’s continuously updated selection of the must-read papers and preprints on COVID-19.
Features & opinion
Owning a car costs way more than you think
Environmental economists surveyed more than 6,000 people in Germany and found that people underestimated the total cost of owning a car by about 50% — and that’s not counting extras, such as financing costs. The researchers suggest that helping people to clock the true cost of their transport choices could reduce car ownership by up to 37% and cut associated transport emissions by 23%.
Deepwater Horizon ‘could happen again’
Ten years after an explosion on a seafloor well killed 11 workers and spilled oil across the Gulf of Mexico, experts say that a similar disaster could happen at any time. The US government has slashed safety regulations that had been implemented in the wake of disaster at the Deepwater Horizon rig — the largest single accidental release of oil and gas into the ocean. “Of course it could happen again, and I think one of the things of most concern is that our ability to control a spill is pretty much the same as it was ten years prior,” says Frances Beinecke, who has served on an independent commission that investigated the disaster.
Read the review article in Nature Reviews Earth & Environment.
Image of the week
Fomalhaut b was thought to be among the few extrasolar planets to have been imaged directly. Then it vanished. Astronomers say it might have been a cloud of dust all along, produced by the collision of two objects about 200 kilometres across. (The Register | 5 min read)
