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Nuclear power plant after sunset. Dusk landscape with big chimneys.

China has more than 50 nuclear power plants with light-water reactors, such as this, but the experimental thorium reactor in Wuwei will be a first.Credit: Getty

Fossil fuels must be left in the ground

Almost all economically viable global coal reserves must remain untapped if we are to have a chance of hitting internationally agreed climate-change goals. An updated model suggests that for us to have a 50% chance of remaining below 1.5 °C degrees of global warming — the more aspirational goal of the 2015 Paris agreement — the world must not emit more than 580 gigatonnes of carbon dioxide before 2100. Under this scenario, 89% of coal reserves, 58% of oil reserves and 59% of gas reserves must remain unextracted. The model also assumes substantial use of carbon dioxide removal and carbon capture and storage, because if they aren’t included — or are included at a smaller scale — “that target is unfeasible”, says environmental and energy economist Dan Welsby.

Nature | 5 min read

Reference: Nature paper

China prepares to test thorium reactor

An experimental thorium-fuelled nuclear reactor is about to begin tests in China. Although thorium has been trialled in reactors before, China looks to be the first country to have a shot at commercializing the technology. The reactor has the potential to produce nuclear energy that is relatively safe and cheap, while also generating a much smaller amount of very long-lived radioactive waste than conventional reactors. Thorium itself is a waste product of the growing rare-earth mining industry and is much more plentiful than uranium.

Nature | 8 min read

MOLTEN-SALT REACTOR. Graphic showing how a molten-salt nuclear reactor works.

Source: US Department of Energy/International Atomic Energy Agency

COVID advances win Breakthrough prizes

Techniques that have helped scientists to understand COVID-19 have scooped two out of five of the most lucrative awards in science and mathematics. “These two awards are for research that has had such an impact on the world that they elevate the stature of the Breakthrough Prize,” says chemical biologist Yamuna Krishnan. “They have been saving lives by the millions.” This year’s US$3-million Breakthrough prizes went to:

• Biochemists Katalin Karikó and Drew Weissman, who discovered how to smuggle genetic material called messenger RNA into cells, leading to the development of a new class of vaccine. Karikó recalls the scepticism surrounding her work in the 1990s that led to numerous grant-proposal and paper rejections (including the 2005 paper for which she is now being recognized), and forced her to take a demotion and a pay cut.

• Chemists Shankar Balasubramanian, David Klenerman and Pascal Mayer, who developed the next-generation sequencing technique that has been used to rapidly track variants of the SARS-CoV-2 coronavirus.

• Chemical biologist Jeffrey Kelly, for working out the part that protein misfolding plays in amyloidosis, a disease that can affect the heart and other organs and cause neurodegeneration — and for developing an effective treatment.

• Optical physicists Hidetoshi Katori and Jun Ye, for inventing the optical lattice clock — a device that would lose less than one second over 15 billion years, improving the precision of time measurements by 10,000 times.

• Mathematician Takuro Mochizuki, for extending the understanding of algebraic structures called ‘holonomic D-modules’ — which are related to certain types of differential equation — to deal with points at which the equations under study are not well defined.

Nature | 6 min read

Ground-breaking carbon capture plant

The largest direct-air carbon capture facility in the world has begun its task of pulling carbon dioxide from the air and entombing it in rocks. The plant, named Orca, is located in Iceland and powered by geothermal energy. It can collect about 4,000 tonnes of CO2 a year — about as much CO2 as is emitted globally every 4 seconds. And it’s expensive: Climeworks, the company behind the plant, sells its carbon offsets for as much as €1,000 (US$1,180) a tonne. But it shows what can be done. “The cost per ton of Orca is perhaps less important than what we will learn, to get quicker to the large scale and ultimately lower prices,” says Jan Wurzbacher, one of Climeworks’ co-founders.

The Financial Times | 4 min read & Bloomberg Green | 6 min read

Features & opinion

How psychological science cleaned house

Ten years ago, the revelation of widespread research fraud by high-profile psychologist Diederik Stapel rocked the field. “What happened next was inspiring,” writes methodologist Jelte Wicherts. “An open debate that went far beyond misconduct and focused on improving research.” In fits and starts, practices improved — often led by early-career researchers. “Now the system must assure them that they can build successful careers by following these methods,” argues Wicherts.

Nature | 5 min read

Five best science books this week

Andrew Robinson’s pick of the top five science books to read this week includes intellectual bees, a doyenne of dark matter and mathematical grief.

Nature | 3 min read