Polynesian navigation stars waves Marshall Islands stick charts

Polynesian sailors navigated by many signs

Early Polynesian sailors crossed open Pacific waters by combining what they observed in the stars, weather, wildlife and waves. They preserved navigation knowledge in memory, and recorded it on instruments such as the Marshall Islands’ stick charts.

Making fertilizer means breaking one of chemistry's toughest bonds

The air is full of nitrogen, but most of it is locked in very stable N₂ molecules that plants cannot use directly. The Haber–Bosch process uses catalysts to help break this strong bond and make ammonia, turning nitrogen from the air into material that can be used for fertilizer.

Burial protected Pompeii’s remains

Nearly 2,000 Years

For nearly 2,000 years, Pompeii lay buried with little air or moisture reaching its remains. Excavation exposed the site to weather, water, light, tourism, and other damage, making it harder to preserve.

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Polynesian navigation stars waves Marshall Islands stick charts

Polynesian sailors navigated by many signs

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