Why does nature create patterns? – the Conversation

Giants Causeway, Northern Ireland (by llee_wu CC BY-ND 2.0 DEED via Flickr).

The reason patterns often appear in nature is simple: The same basic physical or chemical processes occur in many patterned substances and organisms as they form. Whether in plants and animals or rocks, foams and ice crystals, the intricate patterns that happen in nature come down to what’s happening at the level of atoms and molecules…

How deep is the ocean? – the Conversation

Mother humpback and calf (courtesy of NOAA Photo Library CC BY 2.0 via Flickr).

If you wanted to measure the depth of a pool or lake, you could tie a weight to a string, lower it to the bottom, then pull it up and measure the wet part of the string. In the ocean you would need a rope thousands of feet long. In 1872 the HMS Challenger, a British Navy ship, set sail to learn about the ocean, including its depth. It carried 181 miles (291 kilometers) of rope…

Where does beach sand come from? – the Conversation

Pebbles on the Beach (by Susanne Nilsson CC BY-SA 2.0 via Flickr).

Question from Sly M., age 6, Cambridge, Massachusetts…
There’s more to beach sand than meets the eye. It has stories to tell about the land, and an epic journey to the sea. That’s because mountains end their lives as sand on beaches….