The Etymology of the Cosmos: Naming Our Celestial Neighbors

In this episode of Moment of Um, space scientist and communicator Dr. Maggie Aderin-Pocock delves into the fascinating history behind how planets and stars received their identities. By exploring the intersection of ancient mythology and modern astronomy, we gain insight into how humanity has projected its stories onto the night sky for millennia.

The "Wandering Stars" of Antiquity

Dr. Aderin-Pocock explains that the naming of the planets visible to the "naked eye" dates back to the Greco-Roman era. Ancient observers noticed that while most stars remained fixed in their constellations, a few celestial bodies moved independently, leading them to call these objects "wandering stars."

These planets were named after deities from myths and legends, reflecting their physical characteristics:

• Mars: Named after the "god of war" due to its "slightly fiery red colour."
• Mercury: Named for the "messenger of the gods," likely due to its rapid movement and its orbit being "very close to the sun."
• Venus: Often described as a "diamond in the sky," its brilliance inspired the "twinkle, twinkle little star" sentiment, leading to its identification with beauty and light.

Constellations and Mythological Narratives

Beyond the planets, the constellations themselves carry deep cultural histories. A prime example is Delphinus, a constellation named by a Greek astronomer nearly 2,000 years ago. The name, which means "dolphin in Latin," is rooted in Greek mythology. As the story goes, the "sea god Poseidon sent a dolphin to fetch Amphratide, a sea goddess," and the stars are positioned to mimic a dolphin "jumping out of the sea."

The Evolution of Naming: From Myths to Modern Science

While ancient names are steeped in folklore, modern naming conventions for exoplanets—bodies located "way outside of our solar system"—follow a more formal process. Because these planets "can't be seen without a telescope," they remained nameless for much longer.

A turning point occurred in 2015 when the "International Astronomical Union launched a contest" to officially name 14 stars and 31 exoplanets. This process allowed for a more diverse range of honorees, moving beyond ancient gods to historical figures. For instance, the exoplanet Safar was named after the "11th century Spanish Arab astronomer, Ibn al-Saffar," highlighting how modern science bridges the gap between historical contributions and contemporary discovery.

Conclusion

Whether it is the ancient "wandering stars" named for their fiery hues or the modern exoplanets named through international collaboration, the names we give to the universe reflect our enduring desire to understand and humanize the vastness of space. As we continue to look upward, the stories behind these names remind us that the stars are not just cold, distant objects, but vessels for human history, imagination, and scientific progress.