Spectacular stars over Stonehenge and more — August’s best science images

Shooting stars. Stargazers in Salisbury, UK, were treated to a magical sight as the Perseid meteor shower, seen each year when Earth passes through debris left by the comet Swift–Tuttle, rained shooting stars over the prehistoric monoliths at Stonehenge. Astrophotographer Josh Dury spent 3.5 hours photographing the spectacle, and combined 43 images of the meteors, Stonehenge and the Milky Way to create this image. The otherworldly shot was NASA’s astronomy picture of the day on 12 August.

Fixing the unfixable. Cartilage, the strong connective tissue that protects bones and joints, is normally unable to repair itself when damaged, leading to a lengthy recovery process for many injuries. But a new biological material that contains the components needed for cartilage growth can encourage the tissue to regenerate, which could potentially speed up healing. Researchers injected the biomaterial — shown here under a microscope — into damaged cartilage inside sheep’s knee joints, which are a good proxy for human injuries. When treated, the damaged areas were gradually filled in as new cartilage formed. With further development, the material could one day be used to help repair injuries, reduce the need for joint-replacement surgeries and treat conditions such as osteoarthritis.

Dinner time. Underwater photographer Wayne Lai captured the moment a Cape gannet (Morus capensis) dived straight into a circular shoal of sardines off the coast of South Africa, using a strobe light to illuminate the murky waters. The fish had been driven to the surface by dolphins circling underneath, providing a perfect snacking opportunity for the seabird. The shot won the People’s Choice Award in the 2024 Big Picture: Natural World Photography competition.

Microscopic coral. These bizarre, tooth-like structures are actually digestive tissues inside a tiny polyp of brain coral, captured by biologist Patrick Keeling in his laboratory at the University of British Columbia in Vancouver, Canada, using a specialized lens. Coral reefs are made up of thousands of polyps, but a parasite is threatening their health by reducing their ability to survive bleaching — the loss of helpful algae from the corals’ tissues because of stressful conditions. Alongside other researchers, Keeling is studying the parasite to better understand how to protect reefs.

Asteroid origins. This video demonstrates the formation of Dimorphos, a natural satellite (or moonlet) that orbits the near-Earth asteroid Didymos. Astronomers used data from NASA’s 2022 DART mission — which sent a spacecraft to collide with Dimorphos and alter its orbit — to simulate how the system developed. They think that heat from the Sun caused Didymos to spin faster and faster until large chunks of it gradually broke off, which eventually clumped together to form Dimorphos. Although neither the asteroid nor its moonlet is a threat to our planet, learning about their physical properties could help astronauts to divert other, more-hazardous asteroids away from Earth.

Greek tragedy. In mid-August, ferocious wildfires reached the outskirts of Athens after spreading from the nearby town of Varnavas, where the blaze is thought to have been triggered by a faulty electrical pole. Homes, hospitals and monasteries across the region were forced to evacuate, as the flames engulfed buildings and damaged 10,000 hectares of land. Although wildfires in Greece are a yearly occurrence, scientists say they are becoming more intense and frequent because of climate change. The country experienced its hottest June and July on record this year, with unparalleled heat drying out the land and creating the perfect conditions for fire to spread.