Rings, Orbits and Space Storms with Dr. Phil Nicholson

About this episode

Dr. Charles Liu and co-host Allen Liu discuss planetary ring systems and orbital mechanics with Dr. Phil Nicholson.

How do planetary ring systems rings form, and what keeps them in line? What exactly is the Dragon Cloud of Saturn? And what’s up with quasi moon 2025 PN7? To find out, Dr. Charles Liu and co-host Allen Liu welcome Cornell University’s dynamical astronomer Dr. Phil Nicholson for a refresher course in orbital mechanics. As always, though, we start off with the day’s joyfully cool cosmic thing, which is right up Phil’s alley: the recent discovery of quasi moon 2025 PN7. Phil unpacks the orbital mechanics to explain the critical differences between quasi moons and regular moons, and also 2025 PN7’s strange relationship to Earth’s orbit. He also explains the dynamics of the sun’s tidal forces and Earth’s Hill Sphere. For our first question from the audience, Jameson asks, “Are meteorites smaller copies of planets. Are all of them the same?” Rather than discuss meteorites, which are the tiny survivors that have crashed on Earth, Phil pivots to where many of them come from in the first place: asteroids. Really big asteroids share some characteristics with planets, like being spherical in shape, whereas the smaller ones can be highly irregular, like the dumbbell-shaped asteroid 216…

People in this episode

Hosts: Dr. Charles Liu, Allen Liu

Guest: Dr. Phil Nicholson

Topics covered

• planetary ring systems
• orbital mechanics
• quasi moons
• asteroids
• tidal forces

Keywords

• planetary rings
• orbital mechanics
• quasi moons
• asteroids
• tidal forces

Mentioned in this episode

Organizations: Cornell University

Places: Earth, Saturn, 2025 PN7, 433 Eros, 216 Kleopatra, Arrokoth, Ultima Thule

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