Sources & Editorial Approach

Facts are most useful when they are accurate, understandable, and easy to check. We prioritize scientific agencies, public institutions, museums, and specialist educational organizations.

Specific sources for specific facts

Numbered references connect each fact to its source. Important distinctions, approximate values, historical dates, and uncertainty belong with the explanation. We avoid turning a disputed theory into a settled fact.

Corrections

If something looks wrong, send the page address and a supporting reference. Specific evidence makes a correction easier to evaluate.