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Credit: SpaceX

Up, up and away! This video of the successful test flight of the prototype rocket Starhopper was captured on 27 August. SpaceX is now one step closer to its goal of beginning commercial space flights in 2021.

See more of the most spectacular images of the month, as selected by Nature’s photo team.

Nature | A leisurely scroll

Two scientists who discovered the roles of key immune cells have won one of the 2019 Lasker medical-research awards — prizes often dubbed the American Nobels. Immunologists Jacques Miller and Max Cooper, who discovered T cells and B cells, will split the US$250,000 prize for basic medical research.

Nature | 3 min read

US lawmakers have just three weeks to hammer out a 2020 spending deal, which includes funding for major science agencies such as the National Institutes of Health and the National Science Foundation. Science-policy experts are cautiously optimistic that negotiations will be fruitful for research because the government has already decided to boost overall spending. But with control of the country’s legislative bodies split between Republicans and Democrats, much uncertainty remains.

Nature | 3 min read

Weather forecasters in the United States are caught up in a political storm surrounding the predicted path of Hurricane Dorian. The melee kicked off after a tweet by President Donald Trump incorrectly warned that the hurricane threatened Alabama, and the state’s weather forecasting office issued a rebuttal. The New York Times now reports that a senior member of the government successfully pressured leaders at the National Oceanic and Atmospheric Administration (NOAA) to back Trump’s statements over those of its own scientists.

NOAA’s acting chief scientist, Craig McLean, says he will pursue the issue as a potential violation of the NOAA’s rules on scientific integrity. “This intervention to contradict the forecaster was not based on science,” said McLean in an email to his staff, reported by The Washington Post. “It compromises the ability of NOAA to convey life-saving information.”

The New York Times | 6 min read & The Washington Post | 8 min read

FEATURES & OPINION

This year, people aged over 65 began to outnumber those under 5 for the first time in history. But should we seek to eliminate ageing as if it were a disease, or embrace a healthier elderhood as the natural third act of life? Two new books offer very different perspectives on how to adapt to ‘the grey tsunami’.

Nature | 6 min read

After devastating football injuries, chemist Joshua Smith had to learn to walk again. “But instead of focusing on the negatives, I used my rehabilitation as a learning opportunity,” says Smith. He describes how the relentless optimism and self-confidence he gained from playing sports helps him to rebound from scientific failures.

Nature | 4 min read

Scientific publishing is ripe for disruption, argues an editorial in Nature Physics. To understand how, think of the journal as an information platform: in the same way as Uber connects drivers to riders, journals connect scientists to each other as authors, readers and reviewers. Thinking about it that way should help us to grapple with the big question: what is the purpose of a journal today?

Nature Physics | 5 min read

(Nature’s news team — including this Briefing — is editorially independent of its publisher, Springer Nature, which also publishes Nature Physics.)

INFOGRAPHIC OF THE WEEK

Figure 1 | The flight path of monarch butterflies. a, Tenger-Trolander et al.1 studied monarchs (Danaus plexippus) using a flight simulator. In this apparatus, the direction of flight of tethered butterflies is tracked using a video recording device at the base of the simulator. b, When the authors studied wild monarchs reared outside that emerged in the autumn, at a time when wild monarchs normally migrate south, these butterflies flew in a southerly direction, as expected. In the flight-simulator data shown, each line represents the mean flight direction for each butterfly, and longer lines represent a stronger preference. Captively bred monarchs that were reared outside and that emerged in the autumn did not show any specific directional preference in their flight path.

Researchers used a butterfly flight simulator to discover that North American monarch butterflies that are raised in captivity don’t try to migrate by flying south like their wild cousins. These stay-at-home insects wouldn’t help to restore the species if they were released, and could even have negative consequences if they spread versions of genes that thwart migration, writes conservation biologist Karen Oberhauser.

Nature | 6 min read

Reference: Proceedings of the National Academy of Sciences paper