Charon: Love, Myth, and a Cosmic Discovery in 1978

This is your Astronomy Tonight podcast. On this day in astronomical history, July 23rd, we celebrate the anniversary of the discovery of Pluto's largest moon, Charon, in 1978. Picture this: a young astronomer named James Christy is squinting at photographic plates of Pluto at the United States Naval Observatory in Flagstaff, Arizona. He notices something peculiar – a slight bulge on the image of Pluto that seems to move over time. At first, he thinks it might be a defect in the image, but his instincts tell him otherwise. Christy's curiosity leads him down a rabbit hole of investigation, and soon he realizes he's stumbled upon something extraordinary – a moon orbiting the then-ninth planet of our solar system. This discovery was groundbreaking, as it was the first time a moon of Pluto had ever been observed. Now, here's where it gets a bit whimsical. Christy decided to name this new moon Charon, after the mythological ferryman who carried souls across the river Styx to the underworld ruled by Pluto. But there's a twist! The name also honored his wife, Charlene, whose nickname was Char. Talk about romantic astronomy! The discovery of Charon revolutionized our understanding of the Pluto system. We learned that Charon is unusually large compared to Pluto – about half its diameter and one-eighth its mass. This led to the two bodies being classified as a double dwarf planet system, dancing an eternal cosmic waltz around each other. So next time you're stargazing and your thoughts drift to the outer reaches of our solar system, remember Charon – the moon that proved even the smallest, most distant worlds in our cosmic neighborhood can hold big surprises. Don't forget to subscribe to the Astronomy Tonight podcast for more celestial stories and cosmic curiosities. If you want more information, check out QuietPlease.AI. Thank you for listening to another Quiet Please Production. This content was created in partnership and with the help of Artificial Intelligence AI.