Summer briefing: The best of the Briefing

Readers chose the stories that informed, delighted and moved them most this year, from the first-ever image of a black hole to the ultimate limit of human endurance.

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The first image of a black hole shows a bright ring formed by light bending in the intense gravity around the black hole.

Credit: Event Horizon Telescope Collaboration

In April, the first-ever image of a black hole

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)

The limit of human endurance

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.

‘Abandon statistical significance’

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.

Falling for ‘Earth’s evil twin’

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)

Knock-on effects for CRISPR babies

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


How journal editors edit

“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)

Six project-management tips for your PhD

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)

What 50 PIs taught me about why I didn’t get tenure

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)


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


Many of you have written to tell me that your favourite bit of the Briefing is the sign-off at the bottom — which I’m very grateful to hear, since it’s the hardest part to write! Here are some of the links you’ve found most irresistible and thought-provoking:

• Good news! Drinking 25 cups of coffee a day doesn’t stiffen your arteries any more than drinking one — although I’m still not sure it’s such a good idea.

• The Financial Times’s interactive quiz is a fun way to learn why bar charts rule and pie charts drool. (For what it’s worth, I scored a paltry 65%.)

• If it’s taking you a little longer than you had hoped to get tenure, take heart. Nobel-prizewinning former US president Jimmy Carter has only just been granted tenure after 37 years as a professor at Emory University.

I’m currently refreshing my Canadian accent on vacation in the home country, but I hope you still enjoyed this round-up of powerful stories that are definitely worth a second look. We’ll be back to our regular rhythm next week, starting on 19 August. I look forward to returning to a nice big stack of your feedback in my inbox at

In the meantime, why not enter to win the ultimate Apollo LEGO® collection or try your hand at our first-ever cartoon caption contest.

Flora Graham, senior editor, Nature Briefing

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