For thousands of years, people have looked to the sky and tried to make sense of what they saw. Ancient skywatchers tracked the Sun, Moon, planets and stars; later astronomers overturned the idea of an Earth-centered cosmos, discovered new worlds and revealed a Universe far larger than anyone had imagined.
Explore the people, observations and breakthroughs behind our changing view of the cosmos.
Explore the History of Astronomy
Trace astronomy’s journey from the earliest observations of the night sky to the discoveries that opened up the modern Universe.
History of Astronomy
See how our picture of the cosmos evolved from ancient models of the heavens to the vast, dynamic Universe revealed by modern astronomy.
Timeline of Astronomy
Travel through the key dates and events in astronomy, from the ancient world to today’s space telescopes.
Top 10 Greatest Discoveries in Astronomy
Explore ten breakthroughs that fundamentally altered what we know about Earth, the stars and the Universe beyond.
Astronomers Through History
Meet the thinkers and observers who challenged old ideas, made remarkable discoveries and reshaped humanity’s picture of the cosmos.
10 Top Astronomers from the Ancient World
Discover the work of ten pioneering astronomers and mathematicians, from Hipparchus and Ptolemy to Aryabhata and Al-Khwarizmi.
10 Most Influential Astronomers of All Time
From Copernicus and Galileo to Leavitt and Hubble, see how ten remarkable figures left a lasting mark on astronomy.
Discoveries and Changing Ideas
Earth was not always considered a planet, the Sun was not always understood to be a star, and two planets remained unknown until the modern era. Discover how those ideas changed.
Who Discovered the Earth Moves Around the Sun?
See how humanity went from placing Earth at the center of the cosmos to recognizing it as a planet orbiting the Sun.
How Were the Planets of Our Solar System Discovered?
From five wandering lights known to ancient skywatchers to the eight worlds we know today, uncover the story of our planetary system.
Who Discovered the Sun Is a Star?
Find out how the familiar Sun in our sky came to be recognized as one star among countless others.
Explore More Astronomy History
There is much more to astronomy’s past, from ancient instruments and celestial events to calendars, mythology and early attempts to explain the heavens.