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Alex McColgan

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Astrum Space
How Many Moons Does Earth Have?

This image has a few rather spectacular points of interest to see, the obvious one being this channel which cuts through the ground.

Astrum Space
How Many Moons Does Earth Have?

This section here is a lava vent, back when the moon was a lot more geologically active,

Astrum Space
How Many Moons Does Earth Have?

Running out of the vent, in a southwesterly direction, is something known as a rima, or a relay.

Astrum Space
How Many Moons Does Earth Have?

These are channels cut out by lava melting and eroding its way down the slope, kind of like a river on Earth.

Astrum Space
How Many Moons Does Earth Have?

To the east in this image, we see the crater rim of Plato.

Astrum Space
How Many Moons Does Earth Have?

Plato itself was likely filled with lava at some point, as the base is darker and smoother than the regions northwards.

Astrum Space
How Many Moons Does Earth Have?

However, in this image, we can see that a huge section of crust has collapsed down from the crater wall, creating a 24km wide slump block.

Astrum Space
How Many Moons Does Earth Have?

In other words, this section was once connected to the higher plane, however it has since collapsed under its own weight, breaking away and falling somewhat into the crater.

Astrum Space
How Many Moons Does Earth Have?

Let's have a look at one more crater.

Astrum Space
How Many Moons Does Earth Have?

This breathtaking view is from the Apollo 15 mission overlooking Aristarchus crater.

Astrum Space
How Many Moons Does Earth Have?

Aristarchus is seen towards the northwest of the moon, and although Aristarchus is only 40km across, it's bright enough to be seen with the naked eye.

Astrum Space
How Many Moons Does Earth Have?

From Apollo's viewpoint, we can see a really wide angled perspective of the crater.

Astrum Space
How Many Moons Does Earth Have?

Surrounding it are more relays and lava vents, and a small ray system can be seen extending away from the centre.

Astrum Space
How Many Moons Does Earth Have?

From this angle, with the shadow extruding out from the rim, we get a sense of how deep this crater is.

Astrum Space
How Many Moons Does Earth Have?

This complex crater has prominent crater walls, however the uplift found in the centre seems pretty small.

Astrum Space
How Many Moons Does Earth Have?

From LRO's perspective, we have a much higher resolution view of Aristarchus again, and we can have a close examination of the walls and crater base.

Astrum Space
How Many Moons Does Earth Have?

The walls are similar in appearance to Jackson crater,

Astrum Space
How Many Moons Does Earth Have?

However, looking at the peak towards the crater's centre reveals some major differences.

Astrum Space
How Many Moons Does Earth Have?

Not only is the peak much smaller, it also has a banded pattern, exposing layers in the crust that would have otherwise been hidden hundreds of metres down.

Astrum Space
How Many Moons Does Earth Have?

The base of the crater was also likely to have formed from molten lava, rock melted by the impactor.