How does a cloud stay cool under direct sunlight––or seem to vanish in infrared? In nature, phenomena like white cumulus ...

Anaerobic bacteria were among the first life forms on Earth and existed at a time when there was no oxygen in the atmosphere.

Arsenic is a daily poison in many parts of the world, such as Bangladesh where soil has high levels of naturally occurring arsenate. Wells drilled willy nilly by well-meaning organizations ended up ...