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NASA's Mars Perseverance rover acquired this image using its Rover Up-Look Camera.

Credit: NASA/JPL-Caltech

The month’s best science images

This otherworldly photo, taken from the surface of Mars, shows the underside of the sky crane that gently lowered NASA’s Perseverance lander. See more of the month’s sharpest science shots, selected by Nature’s photo team.

Nature | Leisurely scroll

Watch the spectacular video of the Perseverance rover’s jaw-dropping final descent (Nature | 4 min read)

Meteors boost Moon’s comet-like tail

The rate of meteors hitting the Moon seems to affect the brightness of its tail, which is made of sodium atoms and is invisible to the naked eye. During the new Moon, when this moonbeam is focused by Earth’s gravity, special cameras can observe the ‘sodium moon spot’: a bright spot in the sky with a diameter of about 3°. Fifteen years of astronomical observations suggest that the flickering spot is brightest when there are more sporadic meteors, which don’t come in regular showers and can be bigger and speedier.

The New York Times | 4 min read

Reference: JGR Planets paper

See a soft robot swim in the deep

A self-powered soft robot can handle the pressure 10,900 metres deep in the deepest part of the ocean, the Mariana Trench. Taking inspiration from the bones in the skull of the hadal snailfish (Pseudoliparis swirei), researchers used soft materials and distributed electronics to create a machine that can withstand extreme pressure. Its ‘muscles’ contract when an electric current from the robot’s battery is applied, which flaps its two thin side fins. Watch it soar in the latest from Nature Video.

Nature | 6 min video

Go deeper with bioroboticists Cecilia Laschi and Marcello Calisti in the Nature News & Views article (Nature | 6 min read )

Reference: Nature paper

COVID-19 coronavirus update

How to judge pandemic policies

Dozens of efforts to track interventions to curb the spread of COVID have gathered mountains of data. At a workshop last month and a public conference this week, scientists involved in 50 tracking databases met and discussed the mammoth task of compiling and analysing these data. “We still don’t know the best way to plug the data from the tracking systems into mathematical models,” says mathematical physicist Peter Klimek. “But the trackers are a unique treasure trove that we can use to make epidemiological modelling a data-driven science and to prepare for the next pandemic.”

Nature | 5 min read

Coronapod: COVID’s origins

Where did the SARS-CoV-2 virus come from? As a team of researchers from the World Health Organization prepares to report on its investigation into the origins of the virus, Nature reporter Amy Maxmen joins Coronapod to discuss the leading hypotheses and how conspiracy theories gain traction.

Nature Coronapod Podcast | 18 min listen

Subscribe to the Nature Podcast on Apple Podcasts, Google Podcasts or Spotify.

Coronavirus research highlights: 1-minute reads

T cells might show promise against variants

Emerging coronavirus variants do not seem to elude important immune-system players called T cells. Researchers looked at T cells from people who had either recovered from infection with the ancestral SARS-CoV-2 strain or had received an mRNA coronavirus vaccine. Most of the volunteers’ T cells recognized all four variants they were tested against, thanks to viral protein snippets that were unaffected by the variants’ mutations.(Reference: bioRxiv preprint — not peer reviewed)

How to stop kids bringing COVID home from class

Adults living with children — especially secondary-school students — who went into school were more likely to report COVID-19 symptoms or test positive for SARS-CoV-2, according to a large online survey in the United States. Schools could eliminate that risk entirely by implementing at least seven mitigation measures from a list that includes requiring students and teachers to wear masks, preventing parents from entering schools and increasing the spacing between desks.(Reference: medRxiv preprint — not peer reviewed)

A new viral variant hits a COVID-ravaged city

A coronavirus variant detected in the Brazilian city of Manaus might be driving reinfections and the city’s second wave of COVID-19. An estimated two-thirds of Manaus residents were infected with SARS-CoV-2 by October 2020, leading some researchers to predict that population-wide immunity might cause new infections to tail off. But in January 2021, researchers identified a novel coronavirus variant, called P.1, during a period of rising hospitalizations in the city, and they linked the variant to a few cases of reinfection.

(Reference: CADDE CENTRE preprint — not peer reviewed)

Read more about these studies in Nature’s continuously updated selection of the must-read papers and preprints.

Notable quotable

“I believe that one brother, one cousin, one friend at a time, we can educate, reassure and advocate the importance of getting vaccinated.”

Black biomedical scientist Ty Fletcher-Beals shares how she advocates for COVID vaccines to her family and community. (Nature | 5 min read)

Learn to master peer review

Learn to master peer review in a free webcast hosted by Nature Careers editor Jack Leeming. The event will touch on giving constructive, respectful feedback and finding the perfect balance of detail and focus. Sign up to watch the webcast on Thursday 8 April at 15:00 UTC (that’s 7 a.m. PDT, 10 a.m. EDT, 3 p.m. BST and 4 p.m. CEST).