Who discovered Mars? That’s a trick question: Because the planet is visible to the naked eye, humans have been watching our rusty neighbor for thousands of years, and there’s no way to track down the name of the long-dead observer who first noticed its reddish glow.
By Meghan Bartels | SPACE.com
But just because we’ll never be able to give that sharp-eyed human a name doesn’t mean there’s nothing interesting to learn about the history of observing Mars.
Mars, like the other planets visible without a telescope, has caught people’s eyes for its unusual movement against the background constellations. Cultures from the Maya to the Chinese, and from the Aboriginal Australians to the Greeks, left observations of its wandering path across the sky. [Mars at Opposition 2018: How to See It and What to Expect]
That said, they didn’t know what Mars was — it was just a bright light that didn’t behave in quite the same way as the other bright lights did. „These [planets] of course never were regarded, as they are now, as their own separate worlds,“ Anthony Aveni, who studies ancient astronomy in Central and South America and who retired last year as a professor at Colgate University, told Space.com.
Early observers of Mars also prioritized different types of observations of the planet than we do today. Modern astronomers focus on the sidereal year, the time it takes Mars to orbit the sun — about 687 days. But for centuries, Aveni said, that wasn’t the number sky-minded people associated with Mars. „They recognize periodicities and movements that we don’t pay any attention to,“ he said.