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An image of the front of the Large Aperture Telescope Receiver (LATR) just before the final closing.

The front of the Simons Observatory’s Large Aperture Telescope Receiver, the largest receiver for observing the cosmic microwave background built so far.Credit: Mark Devlin/University of Pennsylvania

Observatory will map Big Bang’s afterglow

In a few weeks, a new observatory high in northern Chile’s Atacama Desert will be ready to map the cosmic microwave background (CMB) with unprecedented sensitivity. One of the goals of the Simons Observatory is to find fingerprints left in the CMB by gravitational waves that originated from the Big Bang itself. These would provide incontrovertible evidence for cosmic inflation, a brief moment when the expansion of the early universe is thought to have accelerated hugely. There is no guarantee that the inflation signature, if it exists, is strong enough for the Simons Observatory to detect, says cosmologist Suzanne Staggs, who is the observatory’s co-director. “But oh my gosh — if they were right there, it would be amazing.”

Nature | 7 min read

First pig kidney transplant in a person

A 62-year-old man with end-stage renal failure has become the first living person to receive a pig kidney transplant. The kidney was taken from a miniature pig carrying a record 69 genomic edits, which were aimed at preventing rejection of the donated organ and reducing the risk that a virus lurking in the organ could infect the recipient. So far, the patient is recovering well and the pig kidney is producing urine and showing other signs of a working organ. This early success has raised researchers’ hopes for larger clinical trials involving pig organs. It follows from news last week that surgeons say they have transplanted a genetically modified pig liver into a person for the first time.

Nature | 6 min read

Pregnancy advances ‘biological age’

Studies in mice and humans suggest that being pregnant can increase a person’s ‘biological age’ by a couple of years — but giving birth reverses these changes. Biological age can be estimated from patterns of DNA methylation, which occurs when chemical methyl groups are added to DNA. The patterns reflect the stresses that a body accrues over time. The work supports the idea that “biological age is quite flexible; it’s a fluid parameter. It can go up and down”, says biomedical scientist Vadim Gladyshev.

Nature | 5 min read

Reference: Cell Metabolism paper

Spacecraft will link far side of the Moon

China has launched a spacecraft to the Moon that will act as a communications link between Earth and the lunar far side.Queqiao-2, named after a folktale in which magpies form a bridge across the sky, will support China’s Chang’e-6 mission, set to launch in May. Chang’e-6 aims to become the first mission to collect samples from the far side of the Moon, which is permanently hidden from Earth. Queqiao-2 will also support future Chinese missions to the lunar south pole and will take over from its predecessor, Queqiao-1.

SpaceNews | 3 min read

Read more on Queqiao-1: Chinese satellite launch kicks off ambitious mission to Moon’s far side (Nature | 4 min read, Nature paywall)

Features & opinion

At-home tests without the accuracy trade-off

There is a type of test for infections such as COVID-19 that is almost as accurate as a polymerase chain reaction (PCR) test — which has to be done by a laboratory — and as easy and quick as the rapid antigen tests many of us have used at home. They are ‘isothermal tests’ — so-called because they operate at a consistent temperature, eliminating the need for the repetitive heating and cooling cycles of PCR. They’re comparatively expensive and have stumbled over bureaucratic hurdles. Still, developers are pushing forward, targeting applications such as at-home testing for sexually transmitted infections.

Nature | 10 min read

This article is part of the editorially independent supplement Nature Outlook: Medical diagnostics, produced with financial support from Seegene.

The carbon cost of home-grown veg

A study that looked at home-grown food and community gardens in the United States and Europe unveiled a surprising conclusion: the carbon footprint of food from urban agriculture is six times greater than the conventional, commercial version. Allotmenteers recoiled from the result, but the authors — keen home-growers themselves — emphasize that their findings can help make urban efforts (which have worthwhile social benefits) more carbon-efficient. Upcycling refuse as infrastructure such as raised beds, using equipment for a long time, collecting rainwater for irrigation and practising optimal composting can all help. And for some carbon-intensive commercial products, such as tomatoes, growing locally is already on par with big farms.

BBC Future | 7 min read

Reference: Nature Cities paper

Fresh start for African Academy of Sciences

Peggy Oti-Boateng, a Ghanaian biochemist, and Lise Korsten, a South African food-security researcher, are at the helm of the African Academy of Sciences at a critical time. They have a new strategic plan, with five areas of focus, and a desire to recruit scientists in the African diaspora as members. “We have lost a group of young academics who should have now been leaders on the continent, the professors of the future — and maybe we can partially bring them back,” says Korsten, the academy’s first female president.

Nature | 5 min read

Where I work

Antonia Bornas stands wth sea and a volcano in the background

Mariton Antonia Bornas is chief of the Volcano Monitoring and Eruption Prediction Division of PHIVOLCS in Quezon City.Credit: Dave Tacon for Nature

“We have a lot of natural disasters in the Philippines,” says Mariton Antonia Bornas, pictured here standing next to a monitoring station overlooking Taal volcano, which erupted in January 2020. As chief of the Volcano Monitoring and Eruption Prediction Division, her job is to provide early warning of potential eruptions and to monitor levels of harmful emissions. The hardest part of the job is “dealing with the non-science,” she says. “Responding to people online — even to psychics predicting an eruption — is part of my job and it doubles my work. I have to be a communicator, not just a scientist.” (Nature | 2 min read)

Quote of the day

“We're so species-centric. That's our big blind spot. That's why it's so easy to hack humans.”

Engineer Caleb Chung, who invented Furby — a big-eyed toy that gave the impression of being a sort of proto-chatbot — chimes in on people’s tendency to ascribe personalities to AI systems such as ChatGPT. (The New Yorker | 14 min read)