What is an observatory?
A place built to watch the sky. Some are domes on lonely mountaintops, some are giant metal dishes in radio-quiet valleys, some orbit far above the atmosphere — but they all share one job: collecting the faint light the universe sends our way, and turning it into knowledge.
The many kinds of observatory
Not every observatory looks like a white dome. What an observatory looks like — and where it's built — depends entirely on what kind of signal it's trying to catch. Pick a type to explore it.
One sky, seven kinds of light
Visible light is only a sliver of the electromagnetic spectrum. Each band reveals a different universe — but Earth's atmosphere blocks most of them, which is why observatories end up on mountaintops or in space. Tap a band to see what it shows us.
Why mountaintops?
Air is the enemy of astronomy: it blurs starlight, glows faintly at night, and its water vapour swallows infrared light entirely. The cure is simple — climb above as much of it as you can. Drag the slider to take an observatory up a mountain.
How dark is your sky?
Astronomers rate night-sky darkness on the Bortle scale, from class 1 (a sky so dark the Milky Way casts shadows) to class 9 (an inner-city glow where only the Moon and a handful of stars survive). Slide through the classes and watch the stars disappear.
Five millennia of looking up
Observatories are older than telescopes — older, even, than writing in some places. Click any milestone to expand it.
Test your knowledge
Six quick questions — no pressure, instant answers.
Ready to explore the real thing?