Astronomy chapter 12 (Saturn)

The Roche limit is that distance from a planet where ________.

tidal forces are equal to internal forces *The Roche limit is the tidal stability limit, the critical distance inside of which the moon is destroyed. Only smaller ring particles are found within the Roche limit; larger bodies would be broken up by tidal stress.

What is Saturn orbital period?

29.4 earth years

How does Saturn mass relate to earth?

95x

What substance is underabundant (compared to Jupiter) in the atmosphere of Saturn?

Helium

Why does Saturn have only about half as much helium as a fraction of its total atmospheric composition as do Jupiter, Uranus, and Neptune?

Helium may have liquefied and precipitated down into the interior of Saturn, reducing the overall proportion of helium in the atmosphere.

What is responsible for deleting the outer layers of their helium content?

Helium precipitation

Saturns internal structure from inside out

Icy/rocky core Metallic hydrogen Molecular hydrogen

How is Titan's surface tempurature compared to Earth's

Titan's surface temperature is 94 K, much cooler than Earth's.

Saturn's moon Iapetus has a surface that shows which of the following features?

Two-tone markings *The dark leading face reflects only about 3 percent of the sunlight that reaches it and contrasts strongly with the icy trailing face, which reflects about 50 percent.

Titans atmosphere is mostly made up of?

Nitrogen Methane

Mimas is a moon of Saturn with which of the following characteristics?

A very large impact crater and a role in maintaining one of Saturn's rings *The impact that formed this large crater, called Herschel, may have nearly shattered Mimas.

Roche limit?

Any given planet and any given moon, the critical distance inside of which a moon is destroyed

When is Saturn brightest

At opposition

Where does the Cassini division lie?

Between the A and B rings

The surface temperature of Saturn, though cold, is much higher than would be expected from the amount of solar energy it receives. Which of the following factors is thought to be the primary cause of this higher temperature?

Continued gravitational settling of liquid helium *Because of Saturn's low internal temperature, the liquid helium in its interior condenses to form a continuous helium precipitation that settles toward the planet's core, releasing energy.

In appearance, what immediately distinguishes Saturn from all the other planets?

Its large ring system

Where is the encke gap found?

Outer part of the A ring

Saturn is the ____ most planet

Outermost

Titans interior inside to outside

Rock/ice core High-pressure ice Liquid water Near-surface ice Surface

What is the flattest planet in the solar system?

Saturn

Why is Saturn's atmosphere almost three times thicker than Jupiter's?

Saturn is less massive than Jupiter; its gravity is weaker.

Why is Saturn's atmosphere less varied in color and appearance than Jupiter's atmosphere?

Saturn's top clouds are thicker, with few holes and gaps, and they obscure the deeper layers.

When are saturns rings at their brightest/lowest?

Summer or winter Spring or fall

What two factors enable Saturn to retain its primordial hydrogen?

The planet's large mass (resulting in a high escape speed) and low temperature

Why does the appearance of Saturn's rings change over time as seen from Earth?

The rings lie in the planet's equatorial plane, which is tilted with respect to the ecliptic.

Saturns largest moon?

Titan

What is Saturn rotation rate?

Very rapid and differential (Like Jupiter)

What are Saturns rings primarily made of?

Water ice

Saturn's rings are composed of mainly which of the following?

Water ice *Saturn's rings are composed of many tiny particles, with water ice being the main constituent.