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Credit: Event Horizon Telescope Collaboration

This golden doughnut is the first image ever of the event horizon that surrounds a black hole — in this case, the supermassive black hole at the centre of a nearby galaxy called M87. The image offered a spectacular confirmation of the existence of black holes, first deduced from Albert Einstein’s general theory of relativity 100 years ago. Black holes are widely accepted to exist, but have never before been directly observed. Astronomers created the new image by processing radio-wave observations invisible to the human eye.

“We have seen the gates of hell at the end of space and time,” said astrophysicist Heino Falck. “What you’re looking at is a ring of fire created by the deformation of space-time. Light goes around, and looks like a circle.”

Nature | 9 min read (from April)

NIK SPENCER/Nature; Avery Broderick/University of Waterloo (IMAGES bottom)

Researchers studying ultramarathon runners, Arctic explorers and Tour de France bike racers revealed in June the maximum amount of energy a person can expend for a sustained period of time. It’s around 2.5 times your basal metabolic rate — the amount of energy your body uses while just chilling out. The limit seems to come down to how much food you can digest, rather than anything to do with your heart, lungs or muscles. The real champions: pregnant women, whose energy use peaks at 2.2 times their basal metabolic rate.

BBC | 4 min read (from June)

Reference: Science Advances paper

Number crunch 4,000 calories a day The maximum energy output that an average person can maintain for more than a couple of days.

In March, three statisticians and more than 800 signatories argued for scientists to abandon the entire concept of statistical significance. “We are not calling for a ban on P values,” wrote the researchers. It’s just time to stop bucketing results into ‘statistically significant’ and ‘statistically non-significant’ because of the powerful sway such dichotomies hold on the human mind. “We must learn to embrace uncertainty,” they argue.

Nature | 11 min read (from March)

Statistician Blake McShane tells the Nature Podcast why he co-authored a call to abandon statistical significance.

Source: V. Amrhein et al.

Nearly every space agency in the world is sketching a proposal to explore our long-neglected neighbour, Venus. Once a water-rich Eden, the hellish planet could reveal how to find habitable worlds around distant stars.

Nature | 14 min read (from June)

Biophysicist He Jiankui’s extraordinary claim in November that he had used CRISPR to help make the first babies — twin girls — with edited genomes shocked the world. Many questions remain about the experiments, but among researchers’ chief concerns were the potential effects of the genetic alterations on the girls’ health. The gene that He targeted for its role in HIV is linked to increased severity of other infectious diseases. And an analysis based on genetic and health data from nearly 410,000 people links the mutation to an earlier death.

Nature | 5 min read (from June)

Reference: Nature Medicine paper

SCIENTIFIC LIFE

“As we demand more transparency from our authors, we appreciate that we must also provide more insight into our own editorial processes,” said the editors of Nature Methods in January. They stepped through how they evaluate papers submitted to the journal, from review to publication (or rejection).

Nature Methods | 6 min read (from January)

A PhD project can feel like it demands more time than is humanly possible. In January, PhD candidate Angel Santiago-Lopez came up with a list of project-management skills that could help you tame the beast.

Nature | 3 min read (from January)

Biochemist Bela Schmidt’s quest to understand an all-too-familiar career setback can be distilled into eight pieces of advice. From making a career plan to treating your supervisors as future colleagues, he offers tips to put you in the best position for success.

Nature | 10 min read (from February)

IMAGE OF THE YEAR (SO FAR)

This arresting image of surgeons about to transplant a human face removed from its deceased donor was shortlisted for the 2019 Wellcome Photography Prize in January. “There was complete silence in the room as the surgical team absorbed the gravity of their mission,” says the prize’s description of the image. The face was given to 21-year-old Katie Stubblefield, who became the youngest person ever to receive a successful full face transplant.Lynn Johnson/Wellcome Photography Prize 2019