Rings of Saturn Rings Orbital resonances Commentary

Christiaan Huygens, James Clerk Maxwell astronomy

Rings of Saturn

• Galileo Galilei observed two children of Saturn in 1619.
• “I have observed the most distant planet to have a triple form.”
• In 1656, Christiaan Huygens explained that Saturn was surrounded by thin flat disk.
• “a thin, flat ring, nowhere touching, and inclined to the ecliptic.”
• Astronomers thought the disk consisted of solid or liquid rings.
• Giovanni Cassini discovered a gap in 1675.
• James Clerk Maxwell did the math in 1855
• to prove the rings were made of individually orbiting particles
• that he called “brick-bats.”

Rings

• Colliding moons,
• cataclismic comets,
• asteroidal concussions,
• intricate and dramatic interweavings
• might have spread out Saturn her rings,
• and no one was watching.

Orbital resonances

• Orbital resonances partly explain gaps
• in the rings of Saturn. Moons and moonlets
• shepherd the rings
• like border collies herding sheep,
• like women winding hair about their fingers.