Science
Astronomers Capture Unprecedented Images of Stellar Explosions
Astronomers have successfully captured high-resolution images of two stellar explosions, known as novae, in unprecedented detail. Using a cutting-edge technique called interferometry at the Center for High Angular Resolution Astronomy (CHARA Array) in California, scientists were able to combine the light from multiple telescopes and achieve sharp resolution. The images reveal that these explosions are more complex than previously thought, involving multiple outflows of material and, in some cases, dramatic delays in the ejection process. The study, published in the journal Nature Astronomy, focused on two novae that erupted in 2021: Nova V1674 Herculis and Nova V1405 Cassiopeiae. The images of Nova V1674 Herculis, one of the fastest stellar explosions on record, showed two distinct perpendicular outflows of gas. In contrast, Nova V1405 Cassiopeiae evolved much slower, holding onto its outer layers for over 50 days before finally ejecting them. The observations provide direct evidence that novae are powered by multiple interacting ejections and that the explosion process is more complex than previously thought. The findings challenge the long-held view that nova eruptions are single, impulsive events and instead suggest a variety of ejection pathways. The study's results have significant implications for our understanding of stellar physics, particularly in regards to shock formation and particle acceleration.
NASA Astronaut Jonny Kim and Crewmates Prepare to Return to Earth
NASA astronaut Jonny Kim, along with Roscosmos cosmonauts Sergey Ryzhikov and Alexey Zubritsky, is set to depart the International Space Station aboard the Soyuz MS-27 spacecraft. The crew will undock from the station's Prichal module at 8:41 p.m. EST on December 8 and land on the steppe of Kazakhstan at 12:04 a.m. on December 9. This marks the end of their 245-day mission, during which they orbited Earth 3,920 times and traveled nearly 104 million miles. The space station change of command ceremony will take place on December 7, where Ryzhikov will hand over command to NASA astronaut Mike Fincke for Expedition 74. After landing, the crew members will fly by helicopter to Karaganda, Kazakhstan, and then proceed to their respective destinations. Kim will return to Houston, while Ryzhikov and Zubritsky will depart for their training base in Star City, Russia. NASA will provide live coverage of the crew's return on various platforms, including NASA+, Amazon Prime, and YouTube. The International Space Station has been continuously occupied by humans for over 25 years, serving as a critical testbed for NASA's deep space missions, including the Artemis campaign to the Moon and future human missions to Mars.
Ancient Sea Turtle Fossil Tracks Discovered in Italian Limestone
In 2019, climbers in the Cònero Riviera on the eastern shore of Italy discovered strange tracks on a bed of limestone. The findings were brought to the attention of paleontologist Alessandro Montanari, who recognized the potential significance of the discovery. Montanari and his team used drones to capture images of the tracks, which were found to be similar to ichnofossils, or marks left behind by life forms. The tracks were likely made by a group of medium-sized marine vertebrates paddling towards the southwest on a soft pelagic seafloor. The researchers considered various possibilities, including mosasaurs, plesiosaurs, and sea turtles, as the creators of the tracks. However, they ultimately concluded that the tracks were likely made by a herd of ancient sea turtles that had been frightened off by a sudden earthquake. This theory is supported by the fact that modern sea turtles are known to migrate in herds and sometimes swim close to the seafloor, brushing the sand with their fore-flippers. The earthquake would have released calcilutitic fluxoturbidite, which buried and preserved the soft carbonate sediment and the record of the sea turtle mass exodus. The discovery provides a unique glimpse into the lives of ancient marine animals and highlights the importance of preserving fossil records.
Scientists Develop Smart Material That Changes Colors on Demand
Researchers at the University of Florida have created a revolutionary technique for producing colors that can change instantly. This is achieved through the use of structural colors, which are not created by pigments or dyes, but by the arrangement of physical nanostructures. When light waves hit these nanostructures, they interfere with each other, resulting in the color we see. The team developed a method to make structural colors change by using a material whose properties switch when heated. They stacked a thin layer of vanadium dioxide on top of a reflective aluminum layer, which, when heated, changes from an insulator to a metal, altering the timing of light bouncing from the top and bottom, and thus changing the color we see. This approach produces vivid, reversible color changes on both rigid and flexible surfaces, without the need for complex nanofabrication. The team successfully demonstrated dynamic color switching on large areas of rigid surfaces and flexible materials, including textiles and fabrics. This technology has potential applications in display signage, adaptive camouflage, smart safety labels, and adaptive textiles. The researchers believe that by engineering how the material is grown, they can broaden the color palette and tune the temperature at which the switching occurs. The development of this smart material could lead to innovative products and applications, such as dynamic displays, smart clothing, and adaptive packaging. The ability to change colors instantly and reversibly could also have significant implications for various industries, including fashion, advertising, and technology. Overall, this breakthrough technology has the potential to revolutionize the way we interact with materials and could lead to the creation of new and exciting products.
Scientists Document Over 16,000 Dinosaur Footprints in Bolivia's Carreras Pampas Tracksite
In Bolivia's Torotoro National Park, paleontologists have discovered the world's most extensive dinosaur tracksite, with over 16,600 footprints of theropods, three-toed, bipedal meat-eating dinosaurs. The tracks, found at the Carreras Pampas tracksite, date back to the Cretaceous period, between 101 million and 66 million years ago. The footprints, which cover an area of approximately 80,570 square feet, provide a rare glimpse into the movements and behaviors of these ancient creatures. Many of the tracks are isolated, while others form trackways, indicating that the same animal made multiple impressions. The tracks reveal that the theropods were traveling in different directions, with some moving at a leisurely pace and others sprinting through the muddy shoreline. Over 1,300 tracks also show evidence of swimming in shallow water. The discovery has significant implications for understanding the ancient environments and how dinosaurs and birds used them. The tracks are preserved in what was previously soft, deep mud, which has recorded details of the animals' movements. The varying lengths and widths of the footprints suggest that the dinosaurs ranged greatly in size, from a hip height of about 26 inches to over 49 inches. The site also includes several hundred tracks made by birds that shared the shoreline with the dinosaurs. The study's findings have shed new light on the behavior and ecology of theropods and have raised new questions about the significance of this site and its relationship to other trackway sites in Bolivia.
Atacama Cosmology Telescope's Final Data Confirms "Hubble Tension" in Universe Expansion
The Atacama Cosmology Telescope (ACT) has concluded its nearly 20 years of observations, providing a significant step forward in understanding the evolution of the universe. The final data confirms a complex disparity in measurements of the "Hubble constant," which describes the speed at which the universe is expanding. This disparity, known as the "Hubble tension," arises from differences in measurements taken from the local universe using Type 1a supernovas and those taken from the distant cosmos using "fossil light." The ACT data, which represents observations of the distant cosmos, confirms that the Hubble tension is a real problem. By ruling out many "extended models" of the universe's evolution, the ACT has helped shape the future of cosmology. The ACT made precise measurements of the Cosmic Microwave Background (CMB), a cosmic fossil left over from the Big Bang. The CMB polarization maps collected by ACT have far higher resolution than those collected by the European Space Agency's Planck spacecraft. The comparison of the two datasets is likened to "cleaning your glasses," allowing for a clearer understanding of the universe. The research, available on the arXiv paper repository site, has significant implications for cosmology, confirming that the Hubble constant inferred from the ACT CMB data agrees with that from Planck. This information will help cosmologists make progress in understanding the universe, accepting that something is missing from the standard model of cosmology while eliminating other models.
SpaceX Launches Falcon 9 Rocket from Vandenberg Space Force Base
A SpaceX Falcon 9 rocket was launched from Vandenberg Space Force Base on Thursday, December 4, 2025, at 12:42 p.m. The rocket carried 28 Starlink satellites to low-Earth orbit, which will support Department of War communications. The launch was livestreamed, with coverage beginning about five minutes before liftoff. Following stage separation, approximately eight minutes after launch, SpaceX aimed to land the rocket's first stage booster on a droneship in the Pacific Ocean for potential reuse in a future launch. This launch is part of a series of SpaceX launches from Vandenberg Space Force Base, with the most recent one taking place on Monday evening and another scheduled for Sunday, December 7. The Falcon 9 rocket's launch window was between 10:12 a.m. and 2:12 p.m. on Thursday, and the successful launch marks another milestone in SpaceX's Starlink satellite program. SpaceX has been actively launching Starlink satellites to provide global internet connectivity, and these launches from Vandenberg Space Force Base contribute to this effort. The ability to recover and reuse the rocket's first stage booster is a key aspect of SpaceX's mission to reduce the cost of access to space. With multiple launches scheduled in close succession, SpaceX continues to demonstrate its capabilities in the space industry. The launch of the Falcon 9 rocket and the deployment of the Starlink satellites are crucial for enhancing communication capabilities, particularly for the Department of War.
Frogs Found to be Resistant to Venomous Hornet Stings
Researchers at Kobe University have discovered that the black-spotted pond frog is unharmed by venomous stings from hornets, including the Asian giant hornet. Ecologist Sugiura Shinji conducted a study where individual adult pond frogs were presented with workers of three hornet species under laboratory conditions. The results showed that almost all frogs attacked the hornets, and despite being stung repeatedly, 93%, 87%, and 79% of frogs ultimately consumed the hornets. The frogs showed no noticeable harm even after being stung into the mouth or eyes, demonstrating an extraordinary level of resistance to powerful venom. This resistance could be due to physiological mechanisms such as physical barriers or proteins that block the pain and toxicity of hornet venom. The study suggests that the frogs have developed a double tolerance to these stings, enabling them to successfully prey on hornet workers. The discovery raises important questions for future work, including whether the frogs' tolerance is due to evolved mechanisms or if the hornet toxins are simply not effective in amphibians. The black-spotted pond frog could serve as a valuable model organism for studying the physiological mechanisms underlying venom tolerance and pain resistance in vertebrates. The study was published in the journal Ecosphere, providing new insights into the unique relationship between frogs and hornets.
Astronomers Discover Largest Spinning Structure in the Universe
Astronomers have spotted a massive, spinning branch of the cosmic web that binds 14 galaxies together, potentially making it the largest rotating structure ever discovered. Located 140 million light-years from Earth, the whirling structure is a long, threadlike string of gas that's approximately 5.5 million light-years long and 117,000 light-years wide. The cosmic filament has 14 hydrogen-rich galaxies linked to it in a chain and appears to be rotating at around 68 miles per second. The galaxies around it are also rotating, mostly in the same direction as the gaseous thread, suggesting that structures like this one may play a key role in galaxy formation by influencing the speed and direction of a star cluster's spin. This discovery was made using the MeerKAT array of 64 connected radio telescopes in South Africa. The team suspects that similar rotating filaments will be discovered in the near future as researchers continue to explore the cosmos with next-generation telescopes. The observation is part of the MIGHTEE survey, which is currently ongoing and may shed further light on the filament's behavior or facilitate the discovery of other rotating cosmic threads. The find may also help inform forthcoming surveys from new instruments, like the Vera C. Rubin Observatory in Chile. According to the researchers, this discovery could help us better understand the universe and its formation.
Cold Supermoon to Appear on December 4 as Year's Last Full Moon
The last full moon of 2025, also known as a cold moon due to the typical frigid temperatures of this time of year, will occur on December 4. This event is also a supermoon, where the moon is at its closest point to Earth, known as perigee. The moon will be approximately 357,000 km away, making it the second-closest full moon of the year and the second-largest and brightest. It will be 100 percent illuminated just 12 hours after its perigee and will appear up to 8 percent larger and 16 percent brighter than a normal full moon. The cold supermoon will be particularly high in the sky due to the approaching winter solstice on December 21. The best time to view the moon is during moonrise, when it appears larger than usual due to the lunar illusion. This phenomenon, which still lacks a scientific explanation, is most pronounced during a supermoon. To enjoy the show, find an elevated location with an unobstructed view of the eastern horizon on December 4 at 6:14 pm ET. This event marks the third consecutive supermoon of the year and the last of 12 full moons in 2025. The next supermoon will occur on January 3, 2026, just 12 days after the winter solstice. With clear weather, the cold supermoon promises to be a spectacular ending to the year's astronomical events.