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Technicians in a clean room prepare to install the nearly 10 feet (3 meters) wide dish-shaped high-gain antenna to NASA’s Europa Clipper.

Technicians prepare to install Europa Clipper’s 3-metre-wide antenna on the spacecraft on 17 June at the Kennedy Space Center in Cape Canaveral, Florida.Credit: NASA/Kim Shiflett

Mission to Europa to launch on schedule

NASA has confirmed that its Europa Clipper mission will launch as planned. The news comes after possibly faulty transistors installed on the US$5-billion spacecraft risked causing a significant delay. Now past the final review stage, the mission’s launch window opens on 10 October. If the launch is successful, the orbiter will arrive at Jupiter’s moon in 2030 to investigate its icy crust and the ocean — perhaps harbouring life — that scientists suspect lies beneath it.

Nature | 5 min read

Tiny bone helped humans onto their feet

The lateral fabella, a bone in the knee the size of a sesame seed, might have helped humans to start walking upright. Researchers suggest that the bone, which is found in only 39% of people and linked to osteoarthritis, evolved differently in early humans compared with other primates. The distinct pathway could point to an evolutionary change that helped humans’ ancestors take their first steps on two legs. “People [now] are better nourished, and therefore are taller and weigh more, providing the mechanical stimulus for the bone to form,” says mechanical engineer and co-author Michael Berthaume — which might explain why the bone has become more common in humans over the last 100 years.

Sky News | 3 min read

Reference: Proceedings of the Royal Society B paper

Waves granted legal personhood

The coastal city of Linhares in Brazil has legally recognized its iconic waves as living beings with intrinsic rights. Waves near the mouth of the Doce River have a characteristic tubular break beloved of surfers. They were disrupted in 2015 when an upstream dam collapsed, releasing waste material from an iron ore mine and killing 19 people. Linhares’s new law also protects bodies of water connected to the waves. “When you recognize a little bit of space of the ocean, like these waves, you are reaching the whole ocean,” says environmental lawyer Vanessa Hasson.

Hakai | 4 min read

Amateur astronauts aim for spacewalk

A billionaire who funded much of his own mission could soon become the first non-professional astronaut to step into space. Entrepreneur Jared Isaacman and another civilian astronaut, engineer Sarah Gillis, will attempt the spacewalk on Thursday during SpaceX's Polaris Dawn mission — despite the Dragon capsule’s lack of an airlock (the whole thing will be depressurized before they head out). Yesterday, the mission reached an orbit of 1,400 kilometres from Earth — the farthest people have been since the end of NASA’s Apollo Moon programme.

BBC | 6 min read

Features & opinion

A composite image of fifteen images of iBlastoids with different cellular staining.

Models of human embryos at the blastocyst stage, which are called blastoids.Credit: Monash Univ.

Embryo models broach new ethical territory

Labs across the world are racing to grow the best likeness of a human embryo. Studying stem-cell derived embryo models could demystify the first weeks after conception, helping to address infertility, prevent diseases that emerge early in development and test the safety of drugs for embryos. The field is booming, but as the models become increasingly complex, they are starting to raise ethical questions that are leaving experts scrambling to keep up. The key challenge for researchers who are developing guidelines is determining “when an embryo model would be considered equivalent to an embryo”, says Amander Clark, a developmental and stem-cell biologist.

Nature | 12 min read

Next pandemic could come from the Arctic

“The Arctic is likely to become a hotbed for zoonotic diseases that spill over into humans from other animals,” argues Arctic ecoscientist Christian Sonne. The natural balance is being upset by pollutants, invasive pathogens and melting ice, and ancient microorganisms are also being released as the landscape thaws. He calls for a ‘One Health’ approach that integrates an understanding of the effects on wildlife, humans and ecosystems. For example, food-safety efforts and better disease surveillance could help reduce the risk of spillover events in places where meat is processed by subsistence-hunting communities.

Nature | 5 min read

Lessons from Alzheimer’s drug rejection

In July, the European Medicines Agency (EMA) rejected the clinical use of lecanemab for Alzheimer’s disease. Henrik Zetterberg, a clinical neurochemist who has spent 20 years researching the disease, thinks the EMA made a mistake — partly because it declines advice from scientists who work with industry. “On the surface, this precaution might seem sensible and straightforward, to prevent biased decision-making,” writes Zetterberg. “But researchers with links to the pharmaceutical industry are often best placed to assess new medicines — and many universities see forging links with industry as a key part of a scientist’s job.”

Nature | 5 min read

Image of the week

Underwater view of a Cape gannet bird diving straight into the middle of a circular school of sardines

Credit: Wayne Lai/Big Picture Competition

Underwater photographer Wayne Lai used a strobe light to illuminate the murky waters off the coast of South Africa, and so captured the moment a Cape gannet (Morus capensis) dived straight into a circular shoal of sardines. The fish had been driven to the surface by dolphins circling underneath, providing a perfect snacking opportunity for the seabird. The shot won the People’s Choice Award in the 2024 Big Picture: Natural World Photography competition.

See more of the month’s sharpest science shots, selected by Nature’s photo team. (Wayne Lai/Big Picture Competition)

QUOTE OF THE DAY

“How can we accept in 2024 that people are dying because they don’t have access to a simple bag of oral rehydration salts that cost 50 cents?”

News that cases of cholera are rising — and death rates from the disease are rising even faster — reflects an unacceptable lack of interest in a disease that is easy to prevent and inexpensive to treat, says public-health specialist Philippe Barboza. (The New York Times | 5 min read)