How Stuff Works

Icebergs are made of freshwater. — Icebergs float in saltwater, so you might think they consist of frozen saltwater. Actually, icebergs are made of freshwater. How Icebergs Form Icebergs form on one of two ways: Icebergs form when a large chunk of freshwater ice breaks off or “calves” from an ice shelf or a glacier. This […]

Are Icebergs Made of Freshwater or Saltwater?

This entry was posted on January 30, 2019 by Anne Helmenstine (updated on April 7, 2019)

Shrunken heads in the permanent collection of Ye Olde Curiosity Shop, Seattle, Washington. (Joe Mabel) — Shrunken heads appear in movies and video games, such as Beetlejuice, Harry Potter and the Prisoner of Azkaban, and Diablo 2. People associate shrunken heads with fictitious scary tribes, but the Jivaroan tribes in the Amazon rainforest really did make them. You may be surprised to learn head shrinking occurred […]

How Shrunken Heads Are Made

This entry was posted on January 21, 2019 by Anne Helmenstine (updated on January 30, 2019)

Thermal polish is sometimes sold as mood polish. (Lelê Breveglieri) — Thermal nail polish is a type of polish that changes colors according to temperature. It’s like wearing a mood ring on your nails, except most thermochromic polish only switches between two colors rather than displaying the whole rainbow. The cool (or hot!) effect involves a bit of chemistry. Here’s how […]

How Does Thermal Nail Polish Work?

This entry was posted on December 12, 2018 by Anne Helmenstine (updated on March 12, 2019)

Science can explain the phenomenon of spontaneous human combustion. (Elti Meshau) — Every now and then, there’s a news story about a mysterious death where the victim has burned, seemingly without being set on fire or in proximity to a heat source. In other cases, a fresh corpse began to burn, without external assistance. If forensics rules out obvious causes, like passing […]

Is Spontaneous Human Combustion Possible?

This entry was posted on December 5, 2018 by Anne Helmenstine (updated on March 20, 2019)

Water forms a teardrop shape just before it falls from an object. (Ed Leszczynskl) — If asked to draw a raindrop, just about everyone draws a teardrop shape. When water drips from a surface, like the tip of a leaf, this is the shape it makes just before the drop falls. But, once the drop is released, it forms a sphere. Raindrops form spheres, too, […]

The Real Raindrop Shape Is Not a Teardrop

This entry was posted on November 10, 2018 by Anne Helmenstine (updated on November 24, 2018)

For many people, hair grows faster on one side than on the other. (Christopher Campbell). — Have you ever noticed your hair grows faster on one side than the other? Your stylist may have pointed it out when you went in for a cut or you may have observed it when shaving your face or legs. Your fingernails and toenails may grow faster on one side […]

Why Hair Grows Faster on One Side

This entry was posted on September 27, 2018 by Anne Helmenstine (updated on December 2, 2018)