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The robotic arm of the Perseverance rover working on a rocky outcrop called “Skinner Ridge” in Mars’ Jezero Crater

Perseverance used its robotic arm to collect rock cores from an outcrop called Skinner Ridge, which is part of an ancient river delta on Mars.Credit: NASA/JPL-Caltech/ASU/MSSS

NASA’s Mars rover collects ‘fantastic’ rocks

Since July, NASA’s Perseverance rover has drilled and collected four slim cores of sedimentary rock, formed in what was once a river delta on Mars. They are the first of this type of rock to be gathered on another world — and scientists are excited because at least two of the cores probably contain organic compounds, which, on Earth, are often associated with living things. If all goes well, the samples will be the first ever returned from Mars. They will be picked up by another spacecraft and brought back to Earth no earlier than 2033.

Nature | 5 min read

Millions of children lost parents to COVID

Roughly 10.5 million children worldwide have a parent or carer who died from COVID-19, according to a modelling study. The figure is a dramatic increase on earlier estimates. Epidemiologist and co-author Susan Hillis says decades of research on children whose parents died from AIDS have revealed three ‘accelerators’ that are the foundation for helping children to recover: educational support, economic assistance and assistance for the remaining parent or carer. Identifying the children who need help, and providing it quickly, is key, she says.

Nature | 4 min read

Reference: JAMA Pediatrics paper

ITER fusion facility appoints new chief

Pietro Barabaschi, an electrical engineer who has spent his entire career in fusion research, has been selected to lead ITER, the world’s largest nuclear-fusion experiment. Barabaschi will take over as ITER’s director-general in October, replacing Eisuke Tada, who has served as interim director-general since May. Barabaschi’s past experience makes him well-equipped for the role, says Makoto Sugimoto, who leads Japan’s domestic ITER agency. “I believe he has sufficient knowledge and experience to build ITER.” The US$22-billion project aims to demonstrate the feasibility of fusion power, the energy source behind the Sun that promises near limitless clean energy.

Nature | 3 min read

That's a lot of ants

20 quadrillion

The number of ants on Earth — which outweigh all the wild birds and mammals put together. (The Washington Post | 5 min read)

Reference: PNAS paper

Features & opinion

Air travel needs a radical redesign

The aviation industry produces around one billion tonnes of carbon dioxide per year — comparable to the emissions of Japan, the world’s third-largest economy. But the industry’s current focus on cleaner fuels and carbon offsetting “is a triumph of industrial interests over reality”, argue climate-policy scholars Steffen Kallbekken and David Victor. And it fails to take into account factors such as contrails, the long clouds that form behind aircraft, which might be one of the biggest sources of global warming caused by aviation. Governments and industry must boldly experiment with solutions, such as new propulsion systems and rerouting aircraft, the authors say. “Eliminating aviation’s impact on global warming means upending the industry.”

Nature | 10 min read

CURRENT WARMING AND COOLING EFFECTS OF AVIATION: chart showing warming impacts of emissions from aeroplanes

Source: D. S. Lee et al. Atmos. Environ. 244, 117834 (2021)

Get into deep learning for image analysis

From connectomics to behavioural biology, artificial intelligence is making it faster and easier to extract information from images. A fast-growing array of open-source and web-based tools is making it easier than ever to get started.

Nature | 11 min read

Quote of the day

“It is becoming clear that randomization is a fairer way to allocate grants when applications are too close to call.”

Funders should consider whether to follow in the footsteps of the British Academy, the Swiss National Science Foundation and others in using a lottery to decide between grant applications, argues a Nature editorial.