The Moon Flashcards
What are the Moon’s principle features?
The Sea of Tranquility Ocean of Storms Sea of Crises The crater Tycho The crater Copernicus The crater Kepler The Apennine mountain range
What is the Moon’s diameter?
3 500 km.
What is the Moon’s approximate distance form Earth?
380 000 km.
What is the Moon’s rotational period?
27.3 days.
What is the Moon’s orbital period?
27.3 days.
Why is the far side of the Moon is not visible from Earth?
Because the Moon’s orbital period an its rotational period are the same.
When did we first see the far side of the Moon?
Russian Luna 3
October 1959
Dual lens Camera
What is different about the far side of the compared to the near side?
The near side has a lot of Maria however the far side barely has any. The far side also has a thicker crust.
What differentiates the Maria and the Terra?
Maria are formed by lava flowing in the Moon’s core and when an asteroid/meteor/stellar mass hits the Moon the lava fills up the hole and cools to form flat Maria.
Terra are the lighter rocky terrain that have more craters than Maria.
Why do astronomers believe that the highlands are older than the lunar seas?
Because there are more craters in the highlands than the lunar seas.
Describe rilles.
Rilles are cracks or clefts on the lunar surface notably near maria. They are geological faults caused by collapsed lava tubes. When lava flowed on the Moon, the top and sides of these tubes solidified first while lava flowed underneath. When this lava moved away or cooled, the top or roof of the tube collapsed.
What are wrinkle ridges.
Wrinkle ridges are ridges of maria, usually hundreds of kilometres in length. They are not considered mountains, being only around 200 metres high.
These are thought to have been lava tunnels that contracted and cooled.
Why does the Moon’s gravity affect the Moon’s atmosphere?
The Moon’s gravity is smaller than Earth meaning it can’t have an large atmosphere because there isn’t enough gravity to keep an big atmosphere.
What did the Apollo space program try to achieve?
The Apollo space program was first to make astronauts land on the Moon, explore it and bring back samples of Moon rocks.
What is the the giant impact hypothesis and what evidence backs it up?
A Mars size object crashed into the early Earth, changing its axis and jettisoning debris into its orbit and the Moon formed from this. Evidence for this is that scientists believe the Moon’s crust was molten and an impact would have provided this. Analysis of rock from the Apollo landings confirm the Moon is made of similar material and rock as the Earth from about the same time.
