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The Sycamore quantum processor at the Google Hardware lab

Credit: Rocco Ceselin for Nature

The best science images of the month

Google’s Sycamore processor made headlines last year when scientists said they had achieved ‘quantum supremacy’ — carrying out a calculation that would be near-impossible to do over a reasonable timescale using a classical supercomputer. The above image offers a glimpse into the complicated set-up required to keep Sycamore cool. The processor is installed at the base of a ‘dilution refrigerator’ — a device that can be cooled to extremely low temperatures — alongside filters, amplifiers and cables that run all the way up to room temperature. Blue cables connect the cooled processor to racks of room-temperature electronics that control and read out the qubits, the quantum versions of classical bits.

See more of the year’s best science images, selected by Nature’s photo team.

Nature | Leisurely scroll

150-year-old plankton reveal acid effects

Plankton specimens from the pioneering nineteenth-century HMS Challenger expedition reveal how ocean acidification is weakening the shells of sea life. Researchers compared two species of plankton collected by naturalist Charles Wyville Thomson with modern-day specimens taken from the exact same locations and time of year. On average, modern specimens had thinner shells than the historic specimens — sometimes too thin to image. “I was a little bit shocked to see how dramatic the results were for some species,” says micropalaeontologist Lyndsey Fox.

Science | 4 min read

Iran is not rushing to build a bomb — yet

Iran has admitted that it has a growing stockpile of enriched uranium, prompting fears that the country is building a nuclear bomb. Officials in Iran have denied that they are creating nuclear weapons, and experts say there’s little evidence to suggest they are. The country has complied with the International Atomic Energy Agency’s rigorous inspection regime set out in the 2015 deal between Iran and six global powers that limited its nuclear capabilities in exchange for the lifting of economic sanctions. Because the United States pulled out of the agreement in May 2018, the deal in serious jeopardy. But even if it is scrapped, Iran cannot legally make bombs because it is a signatory of the 1968 Treaty on the Non-Proliferation of Nuclear Weapons.

Nature | 7 min

2019-nCoV coronavirus outbreak latest

• China’s Hubei province, where the the 2019-nCoV coronavirus was first detected, has been subject to an unprecedented quarantine for two weeks. The region’s 60 million inhabitants, including thousands of medical workers from across the country, are part of an unprecedented, and unproven, effort to contain the illness. (Bloomberg News | 15 min read)

• The doctor who warned about the burgeoning coronavirus outbreak has died of the illness. Ophthalmologist Li Wenliang was targeted by police after he told fellow doctors that a SARS-like disease was on the rise at Wuhan Central Hospital. (South China Morning Post | 3 min read)

• Most of the world's supply of masks and respirators, along with any number of other materials essential for health care, comes from manufacturers in China. That creates a vulnerable link in the global supply chain that supports everyday health care in hospitals around the world. (Wired | 8 min read)

• Stay up to date with the latest news on the 2019-nCoV coronavirus outbreak with Nature’s continuously updated coverage.

Notable quotable

“Every day that goes by we know more and every day that goes by we can do better modeling. Unfortunately, this beast is moving very fast.”

Network scientist Alessandro Vespignani ponders possible containment and pandemic scenarios for 2019-nCoV. (Science)

Cancer catalogued

(Steve Gschmeissner/SPL)

Whole-genome sequences for 38 cancers

An interdisciplinary group of scientists from 4 continents has sequenced full genomes from more than 2,600 whole cancer genomes and their matching normal tissues across 38 tumour types. Thanks to these efforts, and previous full-genome sequences, scientists now have an unprecedented view of the genetic changes that can contribute to cancer, and a clearer idea of where gaps in knowledge remain.

• Read an expert summary of the work in the accompanying News & Views article. (8 min read)

Discover the publications in Nature and elsewhere. (Leisurely scroll)

• Learn why this is a turning point for the era of massive cancer sequencing projects in a Nature editorial. (4 min read)

• Hear a call for an international code of conduct for genomics data sharing from eight researchers who were involved in the six-year endeavour. (10 min read)

Read the whole collection

Features & opinion

HARP in action as it vertically and continuously prints a large 3D object.

A resin printer from Chad Mirkin’s lab at Northwestern University in Illinois can create structures as large as a person in hours (image sequence sped up).Credit: Northwestern University

3D printing gets bigger, faster and stronger

Not only is 3D printing becoming faster and producing larger products, but scientists are coming up with innovative ways to print, and creating stronger materials, sometimes mixing multiple materials in the same product. “We can get performance out of these materials that we didn’t think we could get. That’s what’s really exciting to a materials scientist. This is getting people used to the new weird.”

Nature | 13 min read

We don’t know how things fly

Aeronautical engineers (and birds) have no problem coming up with wings that work, and mathematicians have equations that describe the results to a T. But we’re not a lot closer to a complete explanation of the physics at work than Einstein, who said he’d “never encountered a simple answer … even in the specialist literature”. Dig into aerodynamicists’ efforts to illuminate the mystery of lift.

Scientific American | 15 min read

Infographic of the week

Graphic showing mutation burdens in lung cells

Even non-cancerous cells in smokers’ lungs have a high burden of mutations, similar to the mutational profile of lung cancer (shown as grey, with darker colour indicating more mutations). But ex-smokers’ lungs have a substantial fraction of cells that are seemingly unmarked by smoking. How these ‘fresh’ cells arise is a mystery — researchers speculate that they are generated from a population of as-yet-unknown stem cells. The result could explain why ex-smokers’ elevated risk of lung cancer gets lower the longer they abstain. (Nature | 7 min read)

Quote of the day

“For me, it was important to see people that I saw a reflection of myself in, growing up ... To maybe be that source of inspiration for someone else is just such an honour.”

NASA astronaut Christina Koch has completed her 328-day mission on the International Space Station — the longest-ever single spaceflight by a woman. (BBC)