Zombie beetles, smiling turtle and raging wildfires — August’s best science images

Precision printing. Materials scientists have made printed solar cells that are so thin, light and flexible that they can rest on the surface of a soap bubble. Researchers at King Abdullah University of Science and Technology in Saudi Arabia formulated functional ‘inks’ for each layer of the solar-cell architecture that could be applied using an inkjet printer. The electrodes are made of a transparent, flexible, conductive polymer called PEDOT:PSS. Sandwiched between the electrodes is a layer of light-capturing photovoltaic material, and the whole structure is encased in a protective, waterproof polymer coating. The technology could one day be used to make power sources for flexible, lightweight devices such as medical patches, the team says.

High winds. Hurricane Laura left a trail of destruction in Louisiana after it made landfall on 27 August. This overhead shot shows trees that were uprooted by winds of up to 220 km/h in Lake Charles. The storm is one of the strongest ever to hit the state — a category-four hurricane at the time it hit. High winds and flooding killed at least 14 people in Louisiana and Texas, destroyed thousands of homes and left hundreds of thousands of people without water or power.

Oil spill. The coral reefs and pristine lagoons of Mauritius were left smeared with oil after a Japanese-owned cargo ship ran aground on 25 July. The MV Wakashio held 200 tonnes of diesel and 3,900 tonnes of fuel oil, an estimated 1,000 tonnes of which leaked into the sea when the ship’s hull cracked on 6 August. The spill affected a 15-kilometre stretch of the coastline — an internationally recognized biodiversity hotspot. Although local volunteers were quick to rally and much of the oil has been contained in a massive clean-up operation, experts are concerned about the long-term impacts. The spill released a new type of low-sulfur fuel designed to reduce air pollution, and its ecological effects aren't well studied.

Weevil zombies. Here, the fruiting bodies of the parasitic fungus Cordyceps sprout from the bodies of two unfortunate weevils. Nicknamed the ‘zombie fungus’, Cordyceps hijacks the nervous systems of the insects it infects and alters their behaviour, before ultimately killing them. This photo, taken by biologist Damien Esquerré at the Australian National University in Canberra, was the winner in the behavioural and physiological ecology category at the journal BMC Ecology’s annual image contest.

Back from the brink. The ever-smiling Burmese roofed turtle (Batagur trivittata) was presumed extinct just 20 years ago, after unsustainable fishing practices caused their numbers to plummet in Myanmar. But after rediscovering a handful of surviving animals, conservationists have grown the population to nearly 1,000 animals in captivity, some of which have been successfully released into the wild.

Wildfire watch. The 132-year-old Lick Observatory near San Jose, California, narrowly avoided going up in flames after a lightning storm set off hundreds of wildfires across the region in mid-August. As blazes consumed the surrounding hillsides, the Lick — which sits atop Mount Hamilton — appeared to be hemmed in by fire, and the facility was evacuated. Firefighters managed to save all of the main structures, although an unused residence on the grounds was burnt and others sustained water and smoke damage. Founded in 1888, the Lick was the world’s first permanently occupied mountaintop observatory. Over the years its telescopes have allowed astronomers to study the structures of galaxies, black holes and quasars.

Spike proteins. This simulation shows spike proteins (red, yellow, blue and grey) on the surface of the SARS-CoV-2 coronavirus, which it uses to dock onto human cells. Scientists at the European Molecular Biology Laboratory in Heidelberg, Germany, used several techniques including cryo-electron tomography to analyse the molecular structure of the spike protein with near-atomic resolution. Their study revealed detailed features of the protein, including the flexible stalk that connects it to the surface. The proteins are covered in chains of sugar-like polymers (shown in green), which form a protective coat that hides the proteins from antibodies. Researchers have shown that the spike protein can provoke an immune response in humans, so it is of huge interest to vaccine developers.

Synchrotron seedlings. Researchers have used high-energy X-rays to peer inside 20-day-old pine-tree seedlings and study their developing tissues in microscopic detail. They placed living seedlings in a synchrotron and imaged cross sections of their stems to show what happens inside the plant when it is deprived of water. The images show how the different tissues change over about 24 hours. Unexpectedly, the seedling seems to dry up from outside in — as time goes on, dark air pockets appear in the outer tissues (bottom row), while the central core containing the xylem, the plant’s vascular tissue, remains hydrated. “I was completely shocked,” said Dan Johnson at the University of Georgia, who led the work. “The way we thought these seedlings were going to fail, hydraulically, as they dried out, was not at all how they failed.”