History Of Astronomy - Blog Posts

The Very Beginnings of the History of Astronomy

Image credit: Michele Falzone/ Photodisc/ Getty Images

Astronomy in Ancient History

The Very Beginning

Since the beginning of time, humans have looked up at the stars and wondered... But the first documented instance of actual astronomical observations dates all the way back to the Assyro-Babylonians in 1000 BCE. These clever ancient people collected data on celestial bodies and recorded their periodic motions--quite impressive when you consider that the ancient Assyro-Babylonians did not have telescopes or really anything besides their eyes to observe the night sky. 

Ancient Greece

Many ancient civilizations would continue to observe the stars, but it would be the Ancient Greeks who first attempted to use astrometry to estimate the location of celestial bodies in the sky. Copernicus is most well-known for his theory of heliocentrism, but as far back as the third century BCE, some Greek astronomers believed in the heliocentric system. Aristarchus of Samos was one such supporter, and he managed to use trigonometry to assess the relative distance of the Sun and the Moon from Earth. His measurement was not very precise, with him claiming the Sun was 18-20 times the distance of the Moon from Earth (current data puts that number at about 400 times more), but he definitely was on the right track. 

 A century later Greek astronomer Hipparchus of Nicaea created the first stellar catalogue using the ancient Babylonian practice of dividing a circle into 360 degrees and each degree into 60 arc minutes. This original catalog listed the positions of 850 stars to the accuracy of one degree--this might not seem so impressive today, but if you consider he was able to do this based on naked-eye observations and rudimentary gnomons, astrolabes, and armillary spheres. It's also thanks to Hipparchus that we have a magnitude system for describing the brightness of stars. 

The Rest is Ancient History

It would be impossible to list every ancient astronomer who observed something important to astronomy, but needless to say, astronomers from ancient civilizations were all extremely intelligent individuals who collected data and created systems that are still in wide use today.