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Aerial view of gas erupting though to the surface of the Baltic Sea where the Nord Stream pipeline runs

Gas erupting above the Nord Stream pipelines in the Baltic Sea on 27 September.Credit: Xinhua/Shutterstock

Scientists investigate Nord Stream leaks

Researchers are rushing to investigate mysterious leaks in the underwater Nord Stream gas pipelines, which run from Russia to Germany. Nord Stream 2 has been shut since Russia invaded Ukraine in February, but it is still full of gas, which is assumed to be around 90% methane. Leaks have also been reported in the Nord Stream 1 pipeline, which runs alongside it and is currently not operational.

Rough estimates suggest that about 115,000 tonnes of methane might have been released by Nord Stream 2 — equivalent to the annual carbon emissions from two million cars. “If these numbers end up being confirmed, it would be the one of the largest single leaks of natural gas in history in a single location,” says climate scientist Zeke Hausfather. Although huge, that accounts for only around 0.14% of the methane emissions produced globally.Seismologists picked up seismic activity at the same time as the leak that is consistent with explosions, not earthquakes. NATO, among others, has attributed the leaks to sabotage.

Nature | 5 min read

Alzheimer’s drug slows decline in trial

Some researchers are celebrating that a drug candidate for Alzheimer’s disease slowed the rate of cognitive decline for people in a clinical trial by 27%, announced in a press release this week. Others remain cautious over whether the small improvement is meaningful — or whether the study really confirms a controversial theory about the cause of the disease. Developed by Eisai, a pharmaceutical company in Tokyo, and biotechnology firm Biogen in Cambridge, Massachusetts, lecanemab is a monoclonal antibody designed to clear clumps of amyloid-β protein from the brain, which many think are a root cause of Alzheimer’s.

Nature | 5 min read

Reference: Eisai press release (no paper yet)

Fungi inside cancers might affect growth

Two studies have found the clearest link yet between cancer and fungi. In one, researchers catalogued fungal populations in more than 17,000 tissue and blood samples representing 35 types of cancer. As expected, they found that fungi, including several types of yeast, were present in all cancer types that were investigated. But some species were linked to different outcomes, depending on the cancer. In the other study, higher levels of Candida in gastrointestinal tumour cells were linked to more gene activity that promotes inflammation, a higher rate of metastasis and lower survival rates. Researchers note that it’s devilishly hard to avoid contamination in such samples, and more work is needed to determine whether fungi contribute to cancer progression or advanced tumours just create a habitable environment for them.

Nature | 5 min read

References: Cell paper 1 & Cell paper 2

Dinosaur-killer left footprints on the Moon

Researchers studying tiny glass beads in lunar soil samples brought back by China’s Chang’e-5 mission have reconstructed a timeline of asteroid strikes on the Moon — and found that they mirrored impacts on Earth. The finding suggests that asteroid strikes on our planet, including the one that killed the dinosaurs some 66 million years ago, were accompanied by a series of smaller collisions both here and on the Moon. This should make the history of Earth’s bombardment in some ways easier to study: the glass beads, formed by the heat and pressure generated during an asteroid strike, are common on the Moon but harder to find on Earth.

Space.com | 7 min read

Reference: Science Advances paper

Features & opinion

When good works have growing pains

After promising results from early randomized controlled trials, economist Ahmed Mushfiq Mobarak was excited to see a programme to assist landless agricultural workers in Bangladesh roll out to more people. But, at a larger scale, “the outcome was disappointing”, Mobarak writes. “Although this was disheartening, I remain proud of collecting that decision-aiding information: it prevented waste and meant that the limited money for anti-poverty programmes was better spent,” he says. He explains what the Bangladeshi programme taught him about how and why the set of research questions should expand as an intervention is scaled.

Nature | 9 min read

Futures: The one who gets left behind

A conscious space station ponders how to move on from the loss of its crew in the latest short story for Nature’s Futures series.

Nature | 4 min read

Mescaline as medicine

Mescaline, obtained from cacti, has the longest known history of any psychedelic agent. But only now are researchers beginning to investigate its potential as a mental-health treatment in clinical trials. Although generally safe and not addictive, mescaline has low potency and acts over many hours — presenting practical challenges for its use in mainstream health settings. It can also trigger nausea and vomiting. Whatever role mescaline, or any psychedelic, eventually has, therapists emphasize the need to focus on using them as tools in the process of healing, not as a quick fix.

Nature | 9 min read

Nature Outlook: Psychedelic medicine is an editorially independent supplement produced with the financial support of Atai Life Sciences.

Podcast: fish fossils trace the origin of jaws

A wealth of fossils discovered in southern China has shed light onto the diversity of jawed and jawless fish during the Silurian period, more than 400 million years ago. Nature editor Henry Gee explains the finds and what they mean for the history of jawed vertebrates like us.

Nature Podcast | 19 min listen

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Quote of the day

“Just like the industrialized world, we deserve to leave a legacy for our future generations, not just to survive but to thrive.”

Conrod Hunte, deputy chair of the Alliance of Small Island States, joins climate activists and other leaders to explain why funding to address the loss and damage caused by climate change — which mostly affects the people who have contributed least to emissions — is a key issue at the next United Nations climate conference, COP27, in November. (CarbonBrief | 15 min read)