Solar Sytsem

How many moons does Mercury have?

• 1 moon, named Mercury's Companion

• 0 moons

• 2 moons, both discovered by the Mariner 10 mission

• 3 moons, all discovered by the MESSENGER spacecraft

What was the first spacecraft to land on Mars?

• Viking 1

• Mariner 4

• Sojourner

• Opportunity

Which spacecraft were sent to Uranus and Neptune?

• Mariner 9 and Viking 1

• Voyager 1 and Voyager 2

• Cassini and Galileo

• New Horizons and Juno

What are the jovian planets?

• Mercury, Venus, Earth, Mars

• Pluto, Eris, Haumea, Makemake

• Ceres, Vesta, Pallas, Hygiea

• Jupiter, Saturn, Uranus, Neptune

What are the layers of terrestrial planet interiors?

• Crust, Atmosphere, Core

• Mantle, Crust, Core

• Lithosphere, Hydrosphere, Core

• Atmosphere, Mantle, Outer Core

How are craters used to estimate the age of planetary surfaces?

• The more craters, the younger the surface.

• The size of craters determines the age of the surface.

• The fewer craters, the older the surface.

• Craters have no correlation with the age of planetary surfaces.

What determines a planet's ability to generate a magnetic field?

• Its distance from the Sun

• Its size and mass

• The presence of water on its surface

• The number of moons orbiting the planet

Why does Mercury have a thin atmosphere?

• It is too close to the Sun.

• Its small size prevents it from retaining gases.

• Its rapid rotation causes atmospheric escape.

• It lacks geological activity to replenish its atmosphere.

What percentage of the total mass of the solar system does the Sun's mass represent?

• 50%

• 75%

• 99%

• 25%