Reference Terms
from Wikipedia, the free encyclopedia
Foucault pendulum
A Foucault pendulum, or Foucault's pendulum, named after the French physicist Leon Foucault, was conceived as an experiment to demonstrate the rotation of the Earth; its action is a result of the Coriolis effect. It is a tall pendulum free to oscillate in any vertical plane and ideally should include some sort of motor so that it can run continuously rather than have its motion damped by air resistance. At either the North Pole or South Pole, the plane of oscillation of a pendulum remains pointing in the same direction with respect to the fixed stars, while the Earth rotates underneath it, taking one sidereal day to complete a rotation. When a Foucault pendulum is suspended somewhere on the equator, then the plane of oscillation of the Foucault pendulum is at all times co-rotating with the rotation of the Earth. What happens at other latitudes is an intermediate between these two effects.
Related Stories
1
2
Earth & Climate News
September 12, 2025
Sep. 12, 2025 — Forever chemicals known as PFAS have turned up in an unexpected place: beer. Researchers tested 23 different beers from across the U.S. and found that 95% contained PFAS, with the highest concentrations showing up in regions with known water ...
Sep. 12, 2025 — Hidden within Arctic ice, diatoms are proving to be anything but dormant. New Stanford research shows these glass-walled algae glide through frozen channels at record-breaking subzero temperatures, powered by mucus-like ropes and molecular motors. ...
Sep. 11, 2025 — NASA’s Magnetospheric Multiscale Mission has uncovered surprising behavior of pickup ions drifting through the solar wind near Earth. These particles, once thought to be minor players, appear capable of generating waves and influencing how the ...
Sep. 10, 2025 — Barrels dumped off Southern California decades ago have been found leaking alkaline waste, not just DDT, leaving behind eerie white halos and transforming parts of the seafloor into toxic vents. The findings reveal a persistent and little-known ...
Sep. 10, 2025 — Researchers in Germany and Australia have created a simple but powerful tool to detect nanoplastics—tiny, invisible particles that can slip through skin and even the blood-brain barrier. Using an "optical sieve" test strip viewed under a regular ...
Sep. 9, 2025 — Flathead catfish are rapidly reshaping the Susquehanna River’s ecosystem. Once introduced, these voracious predators climbed to the top of the food chain, forcing native fish like channel catfish and bass to shift diets and habitats. Using stable ...
Sep. 9, 2025 — Plants are spreading across the globe faster than ever, largely due to human activity, and new research shows that the very same traits that make plants thrive in their native lands also drive their success abroad. A study of nearly 4,000 European ...
Sep. 9, 2025 — Tiny ocean microbes called Prochlorococcus, once thought to be climate survivors, may struggle as seas warm. These cyanobacteria drive 5% of Earth’s photosynthesis and underpin much of the marine food web. A decade of research shows they thrive ...
Sep. 9, 2025 — New research has revealed that East Antarctica’s vast and icy interior is heating up faster than its coasts, fueled by warm air carried from the Southern Indian Ocean. Using 30 years of weather station data, scientists uncovered a hidden climate ...
Sep. 7, 2025 — Cambridge scientists discovered that thin, weak zones in Earth’s plates helped spread Iceland’s mantle plume across the North Atlantic, explaining why volcanic activity once spanned thousands of kilometers. These ancient scars not only shaped ...
Sep. 7, 2025 — Every year, Panama’s Pacific coast benefits from powerful seasonal winds that drive nutrient-rich waters to the surface, sustaining fisheries and protecting coral reefs. But in 2025, for the first time in at least four decades, this crucial ...
Sep. 6, 2025 — A sweeping new study reveals that humanity has already pushed 60% of Earth’s land outside its safe biosphere zone, with 38% in a high-risk state. By analyzing centuries of data, researchers mapped how human demands on biomass—from farming to ...
Latest Headlines
updated 12:56 pm ET
Sep. 8, 2025 — Once thought to be sailors’ myths, rogue waves gained credibility after a towering 80-foot wall of water struck the Draupner oil platform in 1995. New research shows that these extreme waves ...
Sep. 7, 2025 — Sauropod tooth scratches reveal that some dinosaurs migrated seasonally, others ate a wide variety of plants, and climate strongly shaped their diets. Tanzania’s sand-blasted vegetation left ...
Sep. 6, 2025 — Satellite data reveals sea-level rise has unfolded almost exactly as predicted by 1990s climate models, with one key underestimation: melting ice sheets. Researchers stress the importance of refining ...
Sep. 5, 2025 — A team of chemists has discovered how to transform PET plastic waste into BAETA, a material that captures CO2 with remarkable efficiency. Instead of ending up as microplastics in the environment, ...
Sep. 5, 2025 — UC Santa Barbara researchers project that human impacts on oceans will double by 2050, with warming seas and fisheries collapse leading the charge. The tropics and poles face the fastest changes, and ...
Sep. 5, 2025 — Scientists found that Red Sea corals can endure warming seas but grow much smaller and weaken under long-term heat stress. Though recovery is possible in cooler months, rising global temperatures may ...
Sep. 5, 2025 — Seagrass, a vital coastal ecosystem, may be one of the planet’s best natural carbon sponges—but its fate depends on how we manage nutrients like nitrogen and phosphorus. While moderate nutrient ...
Sep. 4, 2025 — New research reveals that carbon made it possible for Earth’s molten core to freeze into a solid heart, stabilizing the magnetic field that protects our planet. Without it, Earth’s deep interior ...
Sep. 4, 2025 — A Japanese research team successfully harnessed E. coli to produce PDCA, a strong, biodegradable plastic alternative. Their method avoids toxic byproducts and achieves record production levels, ...
Sep. 3, 2025 — Past climate assessments let big polluters delay action, placing more burden on smaller nations. A new method based on historical responsibility demands steep cuts from wealthy countries and more ...