Aristarchus: Biography, Facts & Theory

Instructor: Flint Johnson

Flint has tutored mathematics through precalculus, science, and English and has taught college history. He has a Ph.D. from the University of Glasgow

This essay will discuss the scientist Aristarchus of Samos, the person who first suggested that the Earth and the other visible planets revolved around the sun.

A Statue of Aristarchus, founder of Heliocentrism

Aristarchus' Life

We don't really know much about Aristarchus as a person. He was born in around 310 B.C.E. on the island of Samos, which is off the coast of Asia Minor (i.e., modern-day Turkey). Where and when he was born means he was active during the Hellenistic Age, when Greek culture was traveling to India, Egypt, and dozens of other cultures in the Middle East and southwestern Asia.

We do know one specific thing about Aristarchus' life. At some point in his adult life, he spoke to Cleanthes, the leader of the Stoics, a group of people who worshiped the sun, opposed Heliocentrism, and believed in making decisions without emotions. When he spoke to Cleanthes, Aristarchus jokingly told him he should be charged with impiety. For Aristarchus, someone who believed the Earth was at the center of everything shouldn't worship the sun but the Earth. The comment says a lot about Aristarchus. He was not a spiteful intellect, but more of a sociable person willing to put personal philosophies aside.


Heliocentrism: the Earth orbiting the sun

Aristarchus' biggest contribution was Heliocentrism, the belief that the Earth and the other visible planets traveled around the sun. Before Aristarchus, the Greeks had officially believed that Apollo rode his sun chariot over the Earth during the day. Scholars like Aristotle and Ptolemy had suggested that the sun and the other planets revolved around the Earth, which is also known as geocentrism. Using geometry and astronomical observation, Aristarchus realized that both ideas didn't make any sense and devised heliocentricism as an alternative.

The Stars

Aristarchus had to make all his studies based on what he could see with the naked eye. This meant that he couldn't see small changes in the sky, or any changes made by distant stars. Previous astronomers had thought they were just points of light in the sky, but Aristarchus followed Anaxagoras in suspecting they might be suns just like our own. He just couldn't prove it.

To unlock this lesson you must be a Member.
Create your account

Register to view this lesson

Are you a student or a teacher?

Unlock Your Education

See for yourself why 30 million people use

Become a member and start learning now.
Become a Member  Back
What teachers are saying about
Try it risk-free for 30 days

Earning College Credit

Did you know… We have over 160 college courses that prepare you to earn credit by exam that is accepted by over 1,500 colleges and universities. You can test out of the first two years of college and save thousands off your degree. Anyone can earn credit-by-exam regardless of age or education level.

To learn more, visit our Earning Credit Page

Transferring credit to the school of your choice

Not sure what college you want to attend yet? has thousands of articles about every imaginable degree, area of study and career path that can help you find the school that's right for you.

Create an account to start this course today
Try it risk-free for 30 days!
Create An Account