1.2 The Moon Flashcards
What is the diameter of the moon?
About 3500km (about one quarter of the Earth’s diameter).
Why do we only ever see one side of the moon?
The moon’s rotational period is the same as it’s orbital period.
What is the moon’s rotational period and orbital period?
27.3 days.
On the moon what shade of grey are the Maria (lunar seas) and what shade of grey are the Terrae (highlands/mountains)?
Maria are dark grey and Terrae are light grey.
What is the difference between the near and far side of the moon in terms of features?
There are almost no Maria on the far side, it is almost all mountainous and is more cratered.
What is a rille?
They are narrow, channel-like depressions in the lunar seas. They are believed to be caused by lava flows.
What’s a wrinkle ridge?
A low, sinuous ridge thought to be caused by the buckling of the lunar surface as a result of compressive forces within the cooling, contracting lava.
What is a mascon?
A mascon (mass concentration) is a region of the moons crust that contains a large positive anomaly which means some areas are denser and so there is more gravity in some places then others.
What is a lunar dome?
It’s a type of shield volcano (type of volcano usually built almost entirely of fluid magma flows) that is found on the surface of the Earth’s moon.
How far away is the moon from Earth?
380,000 km (60 radaii).
How long is a lunar month?
29.5 days.
Why is the lunar month 2.2 days longer than the moon’s orbital period?
It takes an extra 2.2 days for the Earth, Sun and Moon to come back into alignment.
Why do we think the highland area of the Moon is older than the low land?
The highland is much more heavily cratered.
What is the lunar cycle?
It is the time it takes for the moon to go through the cycle phases in the sky when observed by earth.
Who put the first men on the moon?
NASA'S Apollo missions (1960) Apollo 11 (1969).
