Who was Hero of Alexandria and what did he invent?

Hero of Alexandria was an ancient Greek mathematician and engineer active during the Roman era. Regarded as the greatest experimentalist of antiquity, he designed pioneering devices like the aeolipile and the earliest land-based windwheel. In mathematics, he is best known for developing a formula to calculate the area of a triangle using only its side lengths.

What we know

• Hero of Alexandria was an ancient Greek mathematician and engineer active during the Roman era, likely in the 1st or 2nd century AD. [1, 2]
• He published a description of a steam-powered device called an aeolipile, also known as Hero's engine. [2, 3]
• Among his inventions was a windwheel, which constitutes the earliest instance of wind harnessing on land. [2]
• He is mostly remembered in mathematics for Heron's formula, which calculates the area of a triangle using only the lengths of its sides. [2]

Still open

• The exact century in which Hero lived remains somewhat uncertain, as he is generally placed in either the 1st or 2nd century AD.

Where to go next

• how it workedWhat was the aeolipile?
• a case in pointHow does Heron's formula work?
• whereWhat was housed in the Library of Alexandria?
• the bigger pictureWho were the Hellenistic scientists of antiquity?
• compared withWhen did Hero live compared to Hypatia?
• an unexpected connectionHow does an ancient engineer connect to the Library of Alexandria?Hero worked and conducted scholarship at the famous Library of Alexandria alongside other prominent historical figures like Eratosthenes.

Sources

• [1]Hero of Alexandria (Wikidata Q161853) · CC0 1.0
• [2]Hero of Alexandria · CC BY-SA 4.0
• [3]Library of Alexandria · CC BY-SA 4.0
• [4]Gabriel Basso · CC BY-SA 4.0
• [5]Hypatia · CC BY-SA 4.0