2026-08-16の世界

Imagine standing on Mars and watching your home planet disappear behind a small, potato-shaped moon. NASA's Perseverance rover recorded exactly that on July 2, using its Mastcam-Z camera. Scientists call this kind of event an occultation, which happens when one object completely blocks another from view. That is different from an eclipse, when an object passes through another's shadow. The rover combined nine images into one sequence, and the final picture shows seven frames, with Earth appearing as a tiny, bright dot sliding behind Phobos, the larger of Mars' two moons. Phobos is only about 27 kilometers wide, and it orbits so close to Mars that it crosses the Martian sky three times a day. At the moment of the picture, Earth was about 195 million miles away. NASA says this is the first time anyone has captured, from the surface of another planet, an image of Earth disappearing behind an object. Justin Maki of NASA's Jet Propulsion Laboratory joked that the picture is "a unique Earth self-portrait... with a Phobos photobomb." Scientists say lining up the two objects perfectly took careful planning, and a little luck.

Off the coast of Queensland, Australia, scientists have filmed wild dolphins doing something rare: using seashells as tools to catch dinner. Researchers from the University of the Sunshine Coast call this behavior shelling. A dolphin chases a fish into a large, empty sea snail shell, lifts the shell to the surface, and shakes it so the trapped fish falls into its mouth. Local boat operators had noticed the trick since 2013, but scientists only recorded it scientifically for the first time between July and October 2025, spotting two separate sightings in the Great Sandy Marine Park near Hervey Bay. Before this, the only published proof of shelling came from a different group of dolphins living more than 3,000 kilometers away, in Shark Bay, Western Australia. In October 2025, the team filmed something even more special: a mother dolphin using a shell, followed minutes later by her calf copying the same move. Lead researcher Alexis Levengood said the moment suggests young dolphins can learn this skill directly from their mothers, not only from other dolphins their own age.

On August 12, American swimmer Katie Ledecky won the women's 1500-meter freestyle at the Pan Pacific Championships in Irvine, California, and the victory meant even more because it happened on home soil. Ledecky finished in 15 minutes and 36.09 seconds, touching the wall 2.53 seconds ahead of Australia's Lani Pallister, who took silver in 15:38.62. The win extended Ledecky's unbeaten streak in this event to more than 15 years, a streak that began with her first international title back in 2013. She now holds the 10 fastest times ever swum in the women's 1500-meter freestyle, an event so long that some fans jokingly call it a "swimming marathon." Even though Ledecky has won gold medals all over the world, this race in California marked her first international medal earned on home soil in the United States. She is scheduled to compete in the 400-meter and 800-meter freestyle events later in the same championships, continuing one of the most dominant runs in swimming history.

Early on August 11, Japan's space agency JAXA launched a new satellite called MICHIBIKI-7 from Tanegashima Space Center. The satellite lifted off at 4:23 in the morning, Japan time, aboard an H3 rocket, flying on the rocket's ninth mission. About 29 minutes after liftoff, ground teams confirmed that the satellite had separated safely and reached its planned orbit. MICHIBIKI-7 is also known as QZS-7, and it belongs to Japan's Quasi-Zenith Satellite System, a network designed to work alongside GPS and give more accurate positioning information across Japan and the wider Asia-Pacific region. Because Japan's cities are full of tall buildings and mountains that can block ordinary GPS signals, these quasi-zenith satellites fly in special orbits so that at least one of them stays almost directly overhead at all times, especially over Japan. Engineers hope the growing satellite network will make everyday tools such as smartphone maps, self-driving cars, and disaster-response systems work more precisely, even in places where normal GPS signals struggle to reach.

Today, one of Tokyo's oldest neighborhoods turns into a giant water fight, and everyone is welcome to join in from the sidelines. The Fukagawa Hachiman Festival takes place at Tomioka Hachimangu Shrine in Koto City, Tokyo, and it is known as one of the three great festivals of Edo, the old name for Tokyo. Local people nicknamed it the "water-throwing festival," because spectators throw buckets of water over the mikoshi, or portable shrines, as bearers carry them through the streets. This year is a special hon-matsuri, a full-scale festival that only happens once every three years, with the last one held in 2023. On August 16, more than 50 neighborhood mikoshi set out from the shrine at around 7:30 in the morning and travel about 8 kilometers through Fukagawa and across the Sumida River. Crowds gather along the route and splash the bearers with water for good luck as the procession passes by. The shrine itself was founded in 1627, so this lively summer tradition has continued for nearly 400 years. Visitors say the mix of noise, water, and heat makes it one of the most refreshing ways to experience old Tokyo in August.

On August 18, a French astronaut will step outside the International Space Station for the very first time, and people around the world will be able to watch it live online. Sophie Adenot, an engineer and former helicopter test pilot, joined the European Space Agency's newest class of astronauts in 2022 after being chosen from more than 22,500 applicants. She arrived at the space station in February 2026 to begin a nine-month mission called epsilon. During the spacewalk, officially known as U.S. Spacewalk 97, Adenot will work with NASA astronaut Anil Menon to replace a Space-to-Ground antenna outside the station. The task is expected to take about 6.5 hours to complete. That antenna carries important voice and data links between the crew and Mission Control in Houston, so keeping it in good condition matters for the whole mission. The task will also make Adenot the first Frenchwoman ever to walk in space. The European Space Agency plans to broadcast the entire event live online, with coverage beginning in the early afternoon in Europe before Adenot exits the station. Before becoming an astronaut, Adenot spent years testing new helicopters and flying rescue missions, logging more than 3,000 flight hours across 22 different aircraft types.

Scientists in Argentina have found the oldest direct evidence that an ancestor of mammals gave birth to live babies instead of laying eggs. The animal is called Chiniquodon theotonicus, a cynodont that lived about 236 million years ago, long before the first true mammals appeared on Earth. A research team led by paleontologist Leandro Gaetano, from Argentina's National Scientific and Technical Research Council, studied a fossil bone under a microscope and found a special growth ring called a neonatal line. This kind of line forms in bone tissue right after an animal is born, so it works like a hidden birth record. By measuring the ring, the team calculated that the baby weighed about 1.7 kilograms at birth, compared with 12 kilograms as a full-grown adult. That ratio, about 14 percent, matches modern mammals that give birth to live young, and it does not match reptiles or birds that hatch from eggs. The discovery pushes back the known start of live birth in the mammal family tree by roughly 90 to 95 million years. Gaetano said the finding shows that live birth probably spread widely among these ancient animals, rather than appearing in just one rare case.

Archaeologists in Egypt have uncovered the remains of an old roadside inn that once welcomed tired travelers crossing the desert hundreds of years ago. The building was found in Asila, a long-buried town in North Sinai, and it stood along the historic Sultani Road, also known as the Pilgrims' Road. That route once connected the Nile Valley with the Arabian Peninsula and the Levant. Merchants, mail carriers, soldiers, and pilgrims heading to Mecca used to stop there to rest, trade goods, and resupply before continuing their journey. The structure, known as a caravanserai, had walls made of mudbrick and red brick, strengthened at the base with large limestone blocks, a common building method from the Islamic era. Pottery found inside, including green-glazed jars and storage vessels, suggests the inn was used during the Mamluk Sultanate, possibly under Sultan Al-Nasir Muhammad ibn Qalawun, who ruled Egypt in the early 1300s, meaning the building is roughly 700 years old. Egypt's Ministry of Tourism and Antiquities called the discovery an important piece of the puzzle for understanding daily life in Sinai long ago. Archaeologist Hisham El-Leithy noted that the building's layout closely resembles another known trading station called Khan al-Khuwaynat.