The customized siege weapon hurls projectiles at 776 mph. The post Man builds supersonic trebuchet in his backyard appeared first on Popular Science .
Source: [Popular Science](https://www.popsci.com/technology/supersonic-trebuchet-video/)
Firefighters raced to save a 1,000-year-old monastery in northeastern Spain on Friday as a growing wildfire prompted the hasty removal of the bones of medieval monarchs buried there.
Basic biology courses teach that cells contain organelles—such as the nucleus, mitochondria and Golgi apparatus—set apart by lipid membranes to get things done. Recent cell biology research has revealed another organizational principle at work in cells across all orders of biology.
When one mentions "waves," we immediately think of a perturbation that propagates. This applies to waves on the shore, sound waves in the air or electromagnetic waves that we use to transmit information via optical fibers. The same idea of propagating perturbations applies to gravitational wave...
"We're not just studying astronomical objects anymore; we're using them to test the laws of nature.
Epithelial cells are the tiny shields that line and protect our bodies. In a developing embryo, epithelial cells grow, divide and move into positions to form the outer layers of our skin and the surfaces of our organs and blood vessels. When we scrape our skin, suffer an internal tear or underg...
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