The Supermassive Podcast · The Royal Astronomical Society

BONUS - Wobbly Planets and Baby Names

·14 min·1 clip

Becky reveals why Earth isn't receding from the sun despite the universe's expansion.

This bonus episode of The Supermassive Podcast features hosts Izzy Clark, Dr. Becky Smethurst, and Dr. Robert Massey answering listener questions. The hosts provide astronomy-themed baby name suggestions and tackle complex cosmic queries. A listener named Adventures of Buckley requested space-inspired baby names, prompting numerous ideas from the hosts. They suggest celestial objects like the moons Ariel, Belinda, and Phoebe, or constellation names like Lyra and Leo. Historical figures such as astronauts Valentina Tereshkova, Yuri Gagarin, and Neil Armstrong are proposed as namesakes. The hosts also mention Louise Webster and Paul Murdin, who discovered the black hole Cygnus X-1, as potential inspirations. Becky clarifies that the expansion of space does not pull apart solar systems or galaxies, which are bound by gravity. She uses an analogy of pier stilts in water to explain how local gravitational forces overcome cosmic expansion. Robert addresses a question from Amanda Gasser about whether a planet could have more than two solstices due to a wobbly axis. He explains Earth's stable axial tilt and contrasts it with Mars, whose tilt varies dramatically over millions of years. Becky fields a question from Yandri Griffin about the controversial "dark flow," an alleged coordinated motion of galaxies. She notes the initial claim from 2008 WMAP data and the subsequent 2013 Planck data analysis that found no evidence. One speculative cause mentioned is the gravitational pull from a neighboring bubble universe in a multiverse. Robert answers Gareth Arnott Muzzley's question about whether energy from stars is lost when they die. He explains energy is conserved but becomes dispersed and irrecoverable, contributing to the universe's eventual heat death. The episode maintains a conversational and educational tone, blending lighthearted discussion with detailed scientific explanations. Listeners interested in astronomy trivia, cosmic thought experiments, and accessible science explanations would enjoy this episode. Those seeking a single, in-depth narrative or breaking news might find the Q&A format less engaging.

As heard by us

A playful mailbox episode that turns a baby-name question into a clear lesson on planetary stability.

The episode opens with a listener's request for astronomy-themed baby names, and that playful setup gives the hosts room to move from jokes into real planetary mechanics.

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Why you'd press play

Want a baby-name detour that turns into a real lesson in planetary wobble?

Read the full recommendation in PlayNext →

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