2026-09-18の世界

Did you know a small icy body far beyond Saturn has its own rings? Its name is Chariklo, and it measures only about 250 kilometers across, far smaller than a planet. Scientists first discovered its two thin rings back in 2013. Now, a team led by astronomer Pablo Santos-Sanz at the Institute of Astrophysics of Andalusia in Spain has made a surprising new discovery. Using the James Webb Space Telescope, the team watched Chariklo pass in front of a distant star on October 18, 2022. This rare event, called a stellar occultation, let the star's light shine through the rings like a spotlight. When researchers compared this fresh data with older observations from the past decade, they found something strange. The inner ring had grown much denser and brighter, while the outer ring had become noticeably fainter. These opposite changes happened in just a few years, an incredibly short time for a planetary ring system. Santos-Sanz said the results force scientists to rethink how such rings form, evolve, and stay stable. This was also the first stellar occultation ever planned specifically for Webb to observe. The discovery shows that even a tiny, icy world can hide surprisingly active and ever-changing rings.

Could a 'weird cat' found on a Bolivian road turn out to be a brand-new species? Yes, it could. In 2016, a local man found a strange kitten near a forest in Bolivia and kept it as a pet. A year later, he gave it to the Senda Verde wildlife sanctuary. Biologist Paola Nogales-Ascarrunz, a National Geographic Explorer, photographed the animal and noticed its spots looked unusual for a tiger cat, a type of small wild cat living in South America. It took years of comparing photos and studying genes to solve the mystery. An international team, including evolutionary ecologist Jonas Lescroart of the University of Antwerp, analyzed complete genomes from 38 tiger cats and margays. They discovered that tiger cats actually belong to five separate species, not just one or two as scientists once believed. The newest species was named Leopardus tilcayo, using its local Bolivian name. It weighs only about 3 pounds, roughly 1.4 kilograms, and split from other tiger cats around 1.4 million years ago. Lescroart said current knowledge comes from just two living cats and a few camera-trap photos. This is the first time in over a century that a completely new wild cat species has been named.

Can one small pendant hold two very different beliefs at once? A team from Novgorod State University in Russia found exactly that. While digging at an old estate in Staraya Russa, a historic town between Moscow and St. Petersburg, archaeologists uncovered a copper-alloy pendant from the 11th century. One side shows a warrior saint, likely Theodore Stratelates, a Roman soldier from the year 281 who was said to have slain a serpent. The other side shows a face surrounded by snakes, similar to the Greek monster Medusa. Researcher Sergei Toropov said the snake image probably does not represent one specific creature. Instead, he explained, it likely stands for a collective symbol of dark forces. This type of double-sided charm is called a zmeevik, and it blends Christian faith with older, pre-Christian protective beliefs. Most known examples from the area date from the 12th to 14th centuries, so this pendant may be the oldest one ever found there. Because it was made of copper instead of gold or silver, archaeologists believe its owner was a middle-class resident, not part of the wealthy elite. Nearby traces of a workshop suggest the pendant was crafted locally.

What if a robot could build a science experiment by itself, any time of day or night? Engineers at MIT have made this possible. Led by physics professor Marin Soljacic, the team built a robotic lab that sets up, adjusts, and takes apart optical experiments without any human help. A seven-jointed robotic arm picks up tiny mirrors, lenses, and light sources, each held in a 3D-printed plastic case with a QR code so the robot can recognize it. A separate Wi-Fi-connected tool then fine-tunes each part's position with incredible precision, down to a fraction of the width of a hair. Overhead cameras watch the whole setup, while software guides every movement and avoids collisions. Normally, scientists spend days or even months carefully lining up mirrors and lenses by hand for a single optics experiment. This new system can run the same kind of setup continuously, day and night, without ever needing a break. Soljacic said, 'A robot isn't going to get bored. It can work 365 days, 24 hours a day.' The team believes the technology could speed up research into solar cells, sensors, video displays, and even future quantum devices. The work was announced on September 17, 2026, and will be presented at a robotics conference later this month.