We can't exactly chat with ancient humans about their lives, but their art gives us glimpses, and a new find in India sheds literal light on a cosmic event they may have witnessed. Quartz cites a new study in the Indian Journal of History of Science in which scientists say a rock painting uncovered in Kashmir may not just be a random image that emerged from its creator's imagination: It could be the region's (and maybe the world's) oldest known drawn sky chart, and the oldest depiction of a supernova as seen through an ancient's eyes. Mayank Vahia's team found the rock art—which shows people and animals underneath what looks like two bright suns in the sky—nestled in a wall in a house that likely existed around 2100BC. The oldest settlement in that region dates back another 2,000 years, so the rock art was probably created at some point in between.
It's those two "suns" that most piqued researchers' interest, though they negated the possibility it was actually two suns, as we've never had more than one, or that the painter was showing the sun and the moon, as those two objects wouldn't both be so bright if they were that close together. Vahia speculated it was a supernova, or "guest star," that may have been close enough to Earth to be visible, so his team scoured astronomical records to see if there'd been a documented supernova during that time. Enter supernova HB9, which would've been viewable from Earth around 3600BC. Vahia even thinks the people and animals shown aren't just random, but depict certain constellations, but he notes more sky charts from that era would need to be found to bolster his theory that this is indeed a sky chart. (One scientist thinks most ancient cave-painters were women.)