AST101: The Sun and Its Neighbours - Class 15: Terrestrial Planets Part 2

A set of flashcards to help review key concepts about terrestrial planets and related geological processes from the AST101 lecture.

What are the main characteristics of terrestrial planets?

Small, rocky, relatively thin or no atmosphere, few moons, made from heavy elements (rock & metal).

What caused craters on Mercury and the Moon?

Craters were created by planetesimals striking the surface at speeds around 100,000 km/hr, leading to explosions.

What period is referred to as the Heavy Bombardment?

A time shortly after planetary formation when there were far more planetesimals, ending about 4 billion years ago.

What are 'Mares' on the Moon?

Areas on the Moon that are covered in fewer craters, indicating volcanic activity has occurred.

How many craters larger than 1km are present on Mars?

There are 384,343 craters larger than 1km on Mars.

What are the surface conditions on Venus as discovered by early probes?

Venus has an atmospheric pressure of 92 bar and a surface temperature of 464 °C.

What significant feature does Olympus Mons represent?

It is the largest volcano in the solar system, located on Mars.

What role does volcanic activity play on Earth compared to other terrestrial planets?

Earth has many active volcanoes, while volcanic activity on the Moon, Mars, and Venus is mostly ended.

What causes erosion on Earth?

Erosion occurs due to flowing water, glaciers, and wind.

What are the consequences of having a low gravity atmosphere on small terrestrial planets?

It allows gas to escape more easily, leading to little outgassing and no significant erosion.