Adler Planetarium and Astronomy Museum - Interprets the exploration of the Universe for the broadest possible audience and hosts one of the finest collections of early astronomical instruments in the world.
Ancient-Skies - Human Cultures and Their Skies - Learn about the IYA2009 global scientific project, which aims to collect and publish available information about various human cultures, their astronomical knowledge, and its representation in the sky within a single web accessible knowledgebase.
Astronomy and World Heritage - Learn how UNESCO and the IAU are working together to promote research and education collaboration as part of UNESCO's Thematic Initiative "Astronomy and World Heritage".
Discovery of the Perseid Meteors - Article from Sky & Telescope magazine on Edward C. Herrick's discovery of the Perseids in 1837.
Historical Celestial Atlases on the Web - Digital editions of various celestial atlases and maps from the middle of the 15th century to the early 20th century.
History of High-Energy Astrophysics - A list of many important dates in the history of high-energy astrophysics and astronomy in general, with links to further details.
Shapley - Curtis Debate in 1920 - Guide to understanding all facets of the Great Debate between Harlow Shapley and Heber D. Curtis over the scale of the universe. Includes a complete transcript.
Starry Messenger - Focuses on the instruments, people, and themes of early astronomy.
