The Aurora Borealis, or Northern Lights, were not "discovered" in the sense of a specific date. They have been observed by humans for millennia.

Here's why:

* Ancient Observations: Historical accounts and cave paintings from cultures around the world, including in Europe, Asia, and North America, depict auroras. These date back thousands of years.

* Scientific Study: While auroras have been observed for a long time, their scientific explanation came later. Galileo Galilei first used the term "Aurora Borealis" in 1619, but it was in the 19th century that scientists began to understand their connection to solar activity and the Earth's magnetic field.

So, while there's no single "discovery" date, humans have been observing and marveling at the Aurora Borealis for a very long time.