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The Curiosity rover is exploring Gale Crater on Mars.NASA/JPL-CALTECH/MSSS/HANDOUT/Getty

NASA’s Curiosity rover has measured the highest level of methane gas ever found in the atmosphere at Mars’s surface. Various spacecraft and telescopes have spotted methane on Mars over the past 16 years, but the gas doesn’t appear in any predictable pattern — deepening the mystery of its origin. On Earth, most methane is produced by living things, spurring the hope that it could have the same lively source on the red planet.

Nature | 2 min read

Extreme weather caused by climate change is undermining the reliability of hydroelectric dams. Drought left millions of people in hydro-dependent Zambia in the dark last month. Meanwhile, wildly fluctuating rainfall in California means that water managers must walk a tightrope between keeping reservoirs from overflowing and maintaining levels in preparation for the next drought.

Bloomberg | 4 min read

Researchers handed in more than 17,000 ‘lost’ wallets to places like post offices and museums in 40 countries to discover that workers there were more likely to contact the owner if there was money inside — and the more money, the more likely. On average, adding a moderate amount (equivalent to US$13.45) to the wallet increased the likelihood of a lost wallet being reported by 11%, and adding a large amount ($94.15) upped it by 26%. The best place to lose your wallet? Switzerland, which had the highest rate of returns, money or no money.

The New York Times | 7 min read

Reference: Science paper


Researchers who tried (and failed) to replicate a provocative study that linked political attitudes with sensitivity to sudden noises and threatening visual images were turned away by Science, the influential journal that published the original paper. “We believe that it is bad policy for journals like Science to publish big, bold ideas and then leave it to subfield journals to publish replications showing that those ideas aren’t so accurate after all,” argue the four scientists, who study the physiological basis of political attitudes.

Slate | 5 min read

References: Rejected replication paper at the Open Science Framework and the original Science paper

US President Donald Trump’s executive order telling federal agencies to cut the number of advisory panels by at least one-third “is the government making itself stupid”, writes Gretchen Goldman, research director of the Center for Science and Democracy at the Union of Concerned Scientists. Goldman argues that the move hurts the country’s capacity for evidence-based decision making, hobbles agencies tasked with protecting people and the environment and reduces the public’s opportunity to give input. All without saving much money — which is ostensibly the point of the order.

Nature | 4 min read

“There was this moment when I realized, I have enough data — I can account for all the plastic humankind has ever made,” says industrial ecologist Roland Geyer in a cartoon-style overview of the world’s plastic problem. More than 6 billion tonnes of it has been thrown away — most of which is still with us, in landfills or the environment.

The Guardian | 6 min scroll


Julia Hawkins, the oldest female American track and field athlete (she is 103 years old, and runs the 100 metres), has some advice for us. (The New York Times)


Cartoon: Person shopping for lab coats says “I just want something that says ‘scientist’ without being so… obvious.

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