Mars has been a source of fascination and speculation ever since the ancient Egyptians observed its blood-red hue and named it for their god of war and plague. But it wasn't until the 19th century when canals were observed on the surface of the Red Planet, suggesting the presence of water, that scientists, novelists, filmmakers, and entrepreneurs became obsessed with the question of whether there's life on Mars.

Since then, Mars has fully invaded pop culture, inspiring its own day of the week (Tuesday), an iconic Looney Tunes character, and many novels and movies, from Ray Bradbury's Martian Chronicles to The Martian. It's this cultural familiarity with the fourth planet that continues to inspire advancements in Mars exploration, from NASA's launch of the Mars rover Perseverance to Elon Musk's quest to launch a manned mission to Mars through SpaceX by 2024. Perhaps, one day, we'll be able to answer the questions our ancestors asked when they looked up at the night sky millennia ago.