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Mars Jezero crater

Jezero crater on Mars was once home to a crater lake and river delta.Credit: NASA/JPL/JHUAPL/MSSS/Brown University

This is where we’ll gather Mars rocks

The first Mars rocks to return to Earth will be gathered from this ancient lakebed (pictured above). NASA has chosen Jezero, a 45-kilometre-wide crater that was once filled with water and might have supported life, as the target for its next Mars rover. The robotic explorer is slated to launch in 2020 and will collect samples that will eventually be retrieved by a future mission.

Nature | 3 min read

Sample populations aren’t to blame for replication crisis

A large-scale effort to replicate results in psychology research has rebuffed the idea that the replication crisis might be partly down to differences in study populations. The project recruited labs around the world to try to replicate the results of 28 classic and contemporary psychology experiments. Only half met the strict P < 0.0001 threshold for significance to be deemed as successfully reproduced, and the diversity of the study populations had little effect. “Those that failed tended to fail everywhere,” says psychologist Brian Nosek, who led the effort.

Nature | 6 min read

Reference: PsyArXiv preprint

Why wombats have cube-shaped poo

Wombats’ stretchy intestines are the reason they are (probably) the only animal in the world that produces cubical faeces. “Wombat intestines have periodic stiffness, meaning stiff-soft-stiff-soft, along the circumference to form cubical faeces,” says mechanical engineer Patricia Yang, who says that the mechanism could inspire new manufacturing processes. Yang shared the 2015 IgNobel prize for determining that nearly all mammals empty their bladders in about 21 seconds.

The Guardian | 5 min read

NIPS is now NeurIPS

A top machine-learning conference that has been dogged by a reputation for sexist behaviour is changing its controversial acronym. The annual Neural Information Processing Systems meeting will now go by the moniker NeurIPS. Researchers had written to the conference saying that the “acronym of the conference is prone to unwelcome puns” and “encourages sexism and is a slur”.

Nature | 3 min read

FEATURES & OPINION

Why extreme weather is getting wetter

From Atlantic hurricanes to Indian monsoons, global warming is already driving more-extreme rains worldwide — along with the flooding, landslides and other devastation they cause. And things will only get worse if greenhouse-gas emissions continue to rise. High-resolution climate models predict that more rains will fall in severe, intermittent storms, rather than in the kind of gentle soaking showers that can sustain crops. Other research indicates that the ways in which thunderstorms organize themselves could change fundamentally, leading to bigger and more-powerful storms. “The next 20 years will be worse than the last 20 years — all indications point to that,” says atmospheric scientist Angeline Pendergrass. “And things will be completely nuts by the end of the century if we keep doing what we’re doing now.”

Nature | 11 min read

Source: E. M. Fischer & R. Knutti Nature Clim. Change 5, 560–564 (2015).

“Enough is enough”

France Córdova, director of the US National Science Foundation, describes why she pioneered the agency’s strict anti-harassment policy — and briefly tells, for the first time, of her own run-in with harassment. Córdova tops a list of established researchers who have witnessed how the myth of science as a perfect meritocracy has failed to live up to the reality. “We were raised with letting the water run off of our back,” says Córdova. “Well, enough is enough.”

The New York Times | 9 min read

Read more: Top US science agency unveils hotly anticipated harassment policy (Nature)

QUOTE OF THE DAY

“Imagine waking up at your house. After eating breakfast, you sit down in a dimly lit room at a table and you look down at a compass never taking your eye off it for the next 12 hours.”

Mountaineer Colin O’Brady describes white-out conditions as he races explorer Louis Rudd to become the first person to cross Antarctica alone and unsupported. (Colin O’Brady on Instagram)

Read more: No one has ever crossed Antarctica unsupported. Two men are trying right now. (The New York Times)