High-speed laboratory images capture two distinct “sandball” shapes formed when raindrops strike dry, sloped sand and roll downhill. (Top) Peanut-shaped sandballs, where grains coat the surface of a liquid core. (Bottom) Donut-shaped sandballs, which densify into rigid, wheel-like structures with a hollow center, enabling far more efficient sediment transport than splash erosion alone.
(Image: Daisuke Noto)
Raindrop-formed ‘sandballs’ that erode hillsides tenfold
Penn geophysicists and colleagues have uncovered Earth-sculpting processes that result from the formation of snowball-like aggregates they call “sandballs.” Their findings provide fundamental insights into erosion and will broaden scientific understandings of landscape change, soil loss, and agriculture.
A typesetting workshop at Penn’s Common Press invited participants to reinterpret lines from the Declaration of Independence as part of the Typography of Independence project and Penn’s America 250 programming.
AI agents could change your life—if they don’t ruin it first
Speaking about AI, Chris Callison-Burch of the School of Engineering and Applied Science says, “The fact that you can interact with your computer in this totally new way and the fact that you can build anything, almost anything that you can imagine—it’s incredible.”
Elon Musk says money can’t buy happiness. Research shows he’s both right and wrong
A study by Matthew Killingsworth of the Wharton School found that happiness and feelings of well-being increased in tandem with a person's rising income.
Pink noise reduces REM sleep and may harm sleep quality
Penn Medicine researchers find that earplugs work better in protecting sleep from traffic noise, challenging the widespread use of ambient sound machines and apps marketed as sleep aids.
Perry World House Distinguished Visiting Fellow Mami Mizutori discusses the upcoming elections and their implications for Japanese policy and politics.
