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Exterior signage on the African Space Agency building in Cairo, Egypt.

The African Space Agency is headquartered in Space City, Cairo.Credit: Ahmed Gomaa/Xinhua via Alamy

Inside Africa’s new space agency

The African Space Agency (AfSA), inaugurated in April, aims to co-ordinate the work of the continent’s more than 20 existing space programmes. The African Union will provide the core of the agency’s funding, with more likely to come from partnerships with China and other space big-hitters. The AfSA will prioritize communication satellites, as well as monitoring satellites to help track climate change, support agriculture and manage natural resources. “We are realistic,” says AfSA space engineer Meshack Kinyua Ndiritu. “We want to walk before we can run.”

Nature | 5 min read

Sierra Leone mpox raises fear of spread

A surge of mpox infections in Sierra Leone has stretched the country’s health-care system, sparking fears that the virus will spread to neighbouring countries in West Africa. Sierra Leone has confirmed more than 3,000 infections in the last month, and an analysis of viral genomes suggests there have been at least four times more infections than officially reported, says genomic epidemiologist Edyth Parker. The recent withdrawal of US funds for foreign aid will make curbing the outbreak even more difficult, experts say.

Nature | 5 min read

Reference: Virological.org analysis

‘Integrity index’ flags metric-chasing unis

A new scoring method — the Research Integrity Risk Index — could make it easier to spot universities that are chasing publishing metrics at the expense of rigorous science. The index categorizes institutions based on how many of their papers are retracted or published in low-quality journals. Such scoring could improve university ranking systems that currently reward quantity of research output over quality. The measure is not designed to identify research misconduct, “but reveal vulnerabilities warranting further review”, says information scientist Lokman Meho, who developed the tool.

Nature | 5 min read

Reference: arXiv preprint (not peer reviewed)

Cutting off rhinos’ horns deters poachers

For years, conservationists in Africa have been taking desperate measures to stop rhino poaching: removing the animals’ horns. Now a study in South Africa reveals that the strategy works, reducing poaching by 78% on reserves where it’s done. “It is kind of a necessary evil,” says biodiversity scientist and co-author Tim Kuiper. “There’s no doubt it saved hundreds of rhinos’ lives.”

Associated Press | 4 min read

Reference: Science paper

Features & opinion

Podcast: Trump’s plans for Mars

Dozens of NASA missions are on the chopping block if the budget proposed by US president Donald Trump comes to fruition. But the enthusiasm for Mars knows no bounds: Trump’s team has proposed spending some US$1 billion in 2026 to prepare for a trip to the Red Planet, but analysts say that the final cost of such a mission could be closer to hundreds of billions of dollars. Nature reporter Alexandra Witze talks to the Nature Podcast about how the pieces fit together, and how they mesh more widely with Trump’s impact on US science.

Nature Podcast Extra | 12 min listen

World Oceans Day

How small-scale fisheries feed the world

Nearly half a billion people’s livelihoods depend, at least partially, on small-scale fisheries: usually individuals, families or small groups of people without access to much capital who catch fish for their own food, or to sell. But data on this huge, relatively invisible work is scattered and patchy. That is now changing, thanks to a research project running since 2017 involving an 800-strong team, including environmental, economic, social, nutritional and governance specialists. Looking at data from 58 countries, they found that small-scale fishers account for around 40% of the global catch and feed approximately 25% of the world’s population.

Start with the Nature editorial (6 min read) or take a look at the whole Illuminating Hidden Harvests collection

What’s up with the Northwest Passage

As winters warm, long-sought routes through the Arctic are opening up to maritime traffic — with potential benefits and downsides for the climate. The number of ships plying Arctic waters, and the distance they travel, is increasing, reports France 24. On top of the economic advantages, shorter journey times mean less carbon emissions. But shipping also brings environmental impacts: black carbon — soot from fossil fuels — darkens the ice and leads to more melting, and vessels discharge sewage, ballast water and litter, and emit underwater noise.

Perhaps counterintuitively, melting is making ice-free conditions harder than ever to predict, as ice fractures and creates shifting choke points. For this reason, along with sanctions against Russia and fraught global geopolitics, large cargo companies are mostly avoiding the Arctic, reports the Financial Times. Several big shipping firms have also pledged to keep out for environmental reasons. “Unless there’s a compelling reason, I think for the time being people will stay away,” says shipping analyst Basil Karatzas.

France 24 | 6 min read & Financial Times | 5 min read

Where I work

Sebastián Gregui sorts through a pile of waste from electrical and electronic devices and reuses the materials.

Sebastián Gregui is the owner of Gregui Pisos y Revestimientos in Tandil, Argentina.Credit: Luciano Gonzalez/Anadolu via Getty

Microwaves, computers and washing machines have one thing in common: the hard plastic ABS, short for acrylonitrile butadiene styrene. In Argentina, Sebastián Gregui’s company grinds up this material — which otherwise is rarely recycled — and incorporates it into concrete to make a material dubbed PlastiHormigón (PlastiConcrete). Each month, the company saves about three tonnes from landfill. “The plastic makes the concrete more flexible, more resistant to heat and cold, and lighter,” says Gregui. “But for us, it’s enough to know that we are doing the right thing.” (Nature | 3 min read)

QUOTE OF THE DAY

“Of all the things you expect to learn from your supervisor, I did not expect my last lessons to be in personal growth and resilience, and in navigating grief and finding purpose.”

During her PhD programme, chemical ecologist Cailyn McKay’s supervisor and mentor passed away. Three months later, her second supervisor also died suddenly. (Nature | 7 min read)