Leap seconds have helped keep clocks synchronized with Earth’s rotation, but their time is now over – here’s why
300 glaciers have disappeared from the American West since the mid‑20th century – the survivors have a few things in common
Read More 5 minute read Engineering Urban trees vs. cool roofs: What’s the best way for cities to beat the heat? Trees like these in Boston can help keep neighborhoods cooler on hot days. Yassine Khalfalli/Unsplash, CC BY Ian… byIan SmithAugust 4, 2025