Terrestrial planets p2

It is difficult to view Mercury from Earth because

• Mercury is very dim.

• Mercury is very small.

• Mercury can't be seen at night.

• Mercury is always very close to the Sun.

How do the atmospheres of the Moon and Mercury compare?

• Mercury's is much denser, like Venus, with much carbon dioxide.

• They are about equal, each only 1% as dense as ours.

• As no spacecraft has yet landed there, no information exists about Mercury's.

• Neither body has a permanent true atmosphere.

The absence of a magnetic field on Venus probably stems from its:

• extremely thick atmosphere.

• high surface temperatures.

• nearness to the Sun.

• slow rotation.

Mercury's evolution was different from the Moon's because:

• Mercury developed a dense atmosphere while the Moon never did.

• Mercury was located farther from Earth, so experienced no tidal forces.

• Mercury was subject to more intense asteroid bombardment than the Moon.

• Mercury developed a weak magnetic field to protect it from solar radiation.

The atmospheric pressure on Venus:

• is much lower than on Earth.

• is about the same as on Mercury.

• is much higher than on Earth.

• causes variations in surface temperature.

What is similar between Venus and Earth?

• They have similar atmospheres and masses.

• They have similar masses and sizes.

• They have similar surface features and sizes.

• They have similar atmospheres and chemical compositions.

Venus' rotation:

• is the fastest of the terrestrial planets.

• is counterclockwise, like the other planets.

• takes longer than its orbit around the Sun.

• axis is highly tilted to its orbital plane, causing large seasonal changes.

Mercury's surface most resembles :

• Earth

• Moon

• Venus

• Mars

Earth and Venus are often called sister planets; in which ways are they most alike?

• atmospheric composition and density

• size, density, and surface gravity

• surface temperature and pressure

• polar caps and rusty red deserts

One of the effects of Mercury's very slow spin is:

• extreme variations in its surface temperature.

• an intensely powerful magnetic field.

• tectonic activity.

• wind patterns that are slow, but global in size.