AST101: The Sun and its Neighbours - Rings and Volcanoes

These flashcards cover key concepts surrounding the Jovian planets, their moons, tidal forces, and geological activity based on the lecture notes.

What are the Galilean Moons?

The 4 large moons of Jupiter, which include Io, Europa, Ganymede, and Callisto.

What is the most geologically active moon in the solar system?

Io, a moon of Jupiter.

What is unique about Europa's surface?

It is covered with un-cratered ice and may have a huge ocean beneath its surface.

What causes Saturn's rings?

They are made up of particles that are less than 0.1 km thick and over 260,000 km in diameter.

Why is Io surprising as a geologically active moon?

Due to its small size, it should have cooled quickly and no longer be geologically active.

What do tidal forces do to Io?

They cause significant heating due to its elliptical orbit and proximity to Jupiter.

What is the reason for tidal locking of the moon?

The tidal force on the moon by the Earth is much larger than the tidal force of the moon on the Earth.

What is the role of the moon Pan in the Encke Gap?

It deflects particles that pass too close to it, creating a gap.

What do the gaps in Saturn's rings indicate?

They are caused by gravitational interactions with moons.

What is the rotation period of Earth now compared to when it formed?

It was 14 hours when Earth formed and is now 24 hours.

What is the expected geological activity of smaller planets like Mercury?

They cool faster and have less geological activity.

What does the composition of Saturn's rings vary with?

It varies with the grain size and the amount of water ice present.

What are tidal forces?

Gravitational forces that cause deformation and heating in celestial bodies, such as Io.

What significant feature does Europa possess beneath its icy surface?

A potential subsurface ocean.

What does the elliptical orbit of Io contribute to?

Greater tidal heating when close to Jupiter compared to when it's farther away.