There's evidence that as far back as 5,000 BCE, Egyptian astronomers were recording the movements of Mars across the sky.

There's no evidence that they had any idea what it was.

An understanding of the planetary nature of Mars would come much, much later, in large part,

because that understanding required a great deal of other larger scale contextual

understandings to be formalized first.

But they did seem to understand that it was different from the other lights in the night sky

in some way.

They noticed its retrograde motion, which basically just means it sometimes seems to move in the opposite direction

of most other objects in the sky, and even included it in some of their ritual tomb-based artwork.

The Neo-Babolonian Empire took this awareness a step further, into greater, if still far from

complete understanding by sometime around 600 BCE.

They figured out a great deal about its cyclical behaviors and invented new

arithmetical methods to adjust their predictions about where Mars and other planets would be

in the sky over time. And at around that same time, the Chinese were figuring out the period and motion of Mars,

among other heavenly bodies, which means, based on observation and math, they'd sorted out

the movement-based relationship between these far-off objects and Earth.

The ancient Greeks didn't do as much

original work related to the planets as those other older groups, in part because they inherited

so much information from the Babylonians, but they did formalize a few conceptions of how all these

objects might fit together, which, though ultimately

incorrect, did give them the chance to discuss and label these sorts of things more formally.

One such name, Planaten, referred to the seven then-known celestial bodies that didn't seem to

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