Unit 2 Chpt 8: Moon & Mercury

In relation to the density of Earth's Moon, Mercury's density suggests that the planet

has a dense metal core.

Compared with the phases of Earth's Moon, Mercury goes from new phase to full phase

more slowly.

Compared with the diameter of Earth's Moon, the diameter of Mercury is

larger.

Compared with the surface of Mercury, the surface of Earth's Moon has significantly

more maria.

Every two times Earth's Moon rotates on its axis, it orbits Earth

exactly two times.

Determine a synchronous orbit.

A synchronous orbit is a situation where an orbiting body spins exactly once for every one time it orbits its parent body.

Why does the Moon have a synchronous orbit around the Earth?

The Moon have the synchronous orbit because, over hundreds of millions of years, tidal forces from Earth have been tugging on the Moon, producing a “drag” that has slowed down the Moon’s spin until one side of the Moon was always facing the Earth.

Planets and moons showing the most craters have

the oldest surfaces.

Compared with the Moon, Mercury has

much larger core.

The most likely theory of the formation of Earth's Moon is that it

formed from a collision of Earth with a Mars-sized object.

On the scale of the 5-billion-year age of the solar system, the Moon is

about the same age as Earth.

Mercury, being smaller than Mars, probably cooled and solidified

faster, because it is smaller.

What is the reason that it is so difficult to view Mercury from Earth?

Mercury is always very close to the Sun.

Mercury has the widest variation in surface temperatures between night and day of any planet in the solar system.

True

What is true of the lunar highlands?

They are the oldest part of the lunar surface.

How does Mercury's rotation relate to the Sun?

Its rotation rate is 2/3 as long as its year, due to tidal resonances.

Mercury presents the same side to the Sun:

every other orbit.

Which of these features is attributed to the shrinking of Mercury's core?

scarps

Mercury's Caloris Basin is aptly named, since:

it is the hottest region, turning to face the Sun when Mercury is at perihelion.

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

dense Mercury had an iron core that shrank, creating the lobate scarps.