Astronomy

A historic observatory precariously perched at the "Top of Europe."

No telescopes, no power, no gift shop: The Observatory of Chichen Itza, one of the world's oldest observatories, takes astronomy back to basics.

An unassuming grey box sitting on San Francisco's Pier 17 is a "sky diary" of the coastal city's temperamental weather.

This historic observatory contains the world's oldest refracting lens telescope.

This abandoned, turn-of-the-century astronomy hub is now the subject of more photographs than it ever took.

One extremely determined man's homemade universe.

Eighteenth-century home, where Herschel discovered the planet Uranus.

Behemoth, cannon-like telescope operated by generations of Irish earls.

A 2,000-year-old computer demonstrates remarkable engineering and astronomical precision.

A set of ancient drawings in the desert of Peru that are so massive, many of them can only be fully seen from the sky.

Every equinox this Maya pyramid puts on a spooky ancient light show.

The world's largest fully steerable radio telescope.