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A stripe of red dots shows the area at risk of a hypothetical asteroid strike.Landsat/Copernicus/Google Earth/Dept. of State Geographer

NASA, ESA and a host of other space agencies are staging a planetary defence drill to prepare for the possibility of an asteroid hitting Earth. Participating scientists and engineers face realistic uncertainties about the fictional space rock’s size, trajectory and risk to the planet. Particularly charming is how everything from ESA’s live tweets to NASA’s webpage is covered in screaming red warnings about how it’s all a drill, so DON’T FREAK OUT.

NPR | 3 min read

Last month, we told you that many leading US universities are breaking the law by failing to make the results of clinical trials public within 12 months. An analysis reveals that the top research universities in Europe are falling short, too. Only 162 of 940 clinical trials (17%) that were due to be published by 1 April had been posted on the European Union’s trials register — and 14 of the 30 universities involved posted nothing at all.

Nature | 4 min read

Reference: Clinical Trial Transparency at European Universities report

After marijuana was legalized in California in 2016, an estimated 1 million people became eligible to have their cannabis-related criminal convictions expunged — but the process isn’t easy. Now, an algorithm developed by a non-profit software company can do the hard work by scanning court documents, identifying eligible cases and filling out the necessary paperwork. Last month, a San Francisco judge cleared the criminal records of more than 8,000 people identified by the software, freeing them from the job, housing and other restrictions that come with being a felon.

BBC | 7 min read

FEATURES & OPINION

The Batagaika crater in eastern Russia was formed when land began to sink in the 1960s owing to thawing permafrost.Credit: Yuri Kozyrev/NOOR/eyevine

The sudden collapse of thawing soils in the Arctic might double the warming from greenhouse gases released from the tundra, warn biologist Merritt Turetsky and her colleagues. As pockets of ice in the permafrost melt, rapid thawing triggers flooding, landslides and erosion that release much more carbon than previously estimated. “Frozen soil doesn’t just lock up carbon — it physically holds the landscape together.”

Nature | 10 min read

Giving up favourite pastimes can also sap your scientific motivation, curiosity and creativity, says PhD student Javad Alizadeh. He explains how he made the hard choices to prioritize a healthy work–life balance at graduate school.

Nature | 4 min read

British poet laureate Carol Ann Duffy presents a series of poems, by herself and others, commissioned in response to the global threat to insect populations. “Everything that lives is connected and poetry’s duty and joy is in making those connections visible in language,” says Duffy.

The Guardian | 16 poems