Picture of Ptolemy
The Bettmann Archive
Ptolemy was a Greek astronomer who lived between 85-165 A.D. He put together his own ideas with those of Aristotle and Hipparchus and formed a unified model of the universe. Ptolemy believed that the Earth was at the center of the universe and all other heavenly bodies circled it, a view which held for 1400 years until the time of Copernicus.
Ptolemy is also famous for his work in geography.
Shop Windows to the Universe Science Store!
Our online store
includes fun classroom activities
for you and your students. Issues of NESTA's quarterly journal, The Earth Scientist
are also full of classroom activities on different topics in Earth and space science!
You might also be interested in:
What types of instructional experiences help K-8 students learn science with understanding? What do science educators teachers, teacher leaders, science specialists, professional development staff, curriculum designers, school administrators need to know to create and support such experiences?...more
Aristotle was a Greek philosopher who lived between 384-322 B.C. He was one of the greatest thinkers of the world and wrote on every major area of thought. Aristotle thought that the Earth was at the...more
Nicholas Copernicus was a Polish asrtonomer who lived between 1473-1543. A long time ago, people believed that the Earth was the center of the universe. Copernicus changed this belief when he introduced...more
Archimedes was a Greek mathematician and engineer who lived between 287-212 B.C. His greatest contributions are in the field of geometry, where he did much work with circles and their properties. Legend...more
Democritus was a Greek philosopher who lived between 470-380 B.C. He believed that everything in the universe was made up of tiny, indestructible particles called atoms. Democritus had many remarkable...more
Eratosthenes was a Greek scientist. He lived from 276 to 194 B.C. He studied astronomy, geography, and math. Eratosthenes is famous for making the first good measurement of the size of the Earth. He lived,...more
Plato was a Greek philosopher who lived between 427-327 B.C. He founded the Academy in Athens, a school which made many important scientific discoveries in ancient times. Plato believed that knowledge...more
Ptolemy was a Greek astronomer who lived between 85-165 A.D. He put together his own ideas with those of Aristotle and Hipparchus and formed a unified model of the universe. Ptolemy believed that the...more