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Quickie Questions - Moon Madness - Interior/Surface

Date Answered Questioner (age, location) Question Answer

July 7, 2008ernie (age 12, sd) what are the round pits on the surface of the moon called? The two main areas of the moon are called the Maria and the Highlands. Both exhibit large (circular) craters that are the result of meteor impacts.
April 14, 2008Hai (age 6, California, USA) Why does Earth's moon encompass an inactive core while Earth itself accomodates an active core? The Moon did have a molten core and magnetic field millions of years ago, but it doesn’t have one now. The most prevalent theory about the formation of the Moon is the Giant Impact (the proto-Earth was hit by a Mars-sized body and our moon formed from the debris). This theory is supported by the lack of a sizeable nucleus. Had the Moon been formed by accretion of smaller objects, we would expect the existence of a significant core.
May 5, 2007jessica (USA) Describe the moons geological history? Scientists have studied the ages of rocks in cratered regions and have determined the rate of cratering at various epochs in the Moon's past. By studying the light-colored highlands, they found that there was a period of heavy bombardment very early in the Moon's history, from about 4.6 to 3.8 billion years ago. After that, the rate dropped off substantially and much less cratering has occurred since then. Rock samples from large impact basins show that about 3.1 to 3.8 billion years ago several asteroid-size objects impacted the Moon, just as the period of heavy bombardment was ending. This was shortly followed by lava flows which filled in the basins and formed the dark maria. This explains why craters are relatively few and isolated on the dark maria, but dense and overlapping in the highlands. No lava flows occurred on the highlands to erase the original blanket of craters from the time when the Moon's surface was showered with the debris of the early solar system. The far side of the Moon has only one small maria. So lunar geologists believe that the far side is very representative of how the Moon looked 4 billion years ago. From our web page The Moon's Geological History.
February 5, 2007joyce (philippines) what is the hole structure of the moon While there are only two basic types of regions on the Moon's surface, there are many interesting surface features such as craters, mountain ranges, rilles, and lava plains. The structure of the Moon's interior is more difficult to study. The Moon's top layer is a rocky solid, perhaps 800 km thick. Beneath this layer is a partially molten zone. Although it is not known for certain, many lunar geologists believe the Moon may have a small iron core, even though the Moon has no magnetic field. By studying the Moon's surface and interior, geologists can learn about the Moon's geological history and its formation. MOre about our Moon can be found at The earth's moon.
August 8, 2001 Harry (New Zealand) What are the average temperatures of the sunlit side and the dark side of the Moon? On the sunlit side, the average temperature is around 100 deg C, while on the dark side the average temperature is a very cold -173 deg C.
July 13, 2000 Rebecca (New York, USA ) Why are there still craters on the moon from early history preserved on the surface while on earth the surface bears little remenance of asteroid impact?

The Moon doesn't have any weather. This means there isn't any rain, wind or other force to disturb the surface of the Moon. Even the footsteps left by astronauts will remain for many years!

July 13, 2000 Tracy (Virginia, USA ) Why was the Moon's surface dust so much less then predicted?

In order to have dust, you need two important ingredients: fine-grained substances and wind. The Moon has neither.

Instead, the Moon is made mostly of heavy elements, like iron and magnesium. It is also made of rock, rather than fine-grained particles like sand.

More importantly, the Moon doesn't have any weather, which means it doesn't have any wind. If there isn't any wind, then there is nothing to stir the loose dirt up!

May 8, 2000 Alexander (United Kingdom) Is it possible for moonquakes to be caused by radio waves traveling through space? Since radio waves are vibrations I thought these vibrations could cause a small quake in the moon.

Moonquakes originate in the Moon's core, which is more than a 1000 kilometers down. It is very unlikely that radio waves can penetrate to this level. Scientists use radio waves to monitor weather, national defense and space exploration.

Probes, like the Lunar Prospector, use radio waves as their "eyes". Waves are sent to the surface, bounce off and return to the probe. The surface of the object can be tested this way.

May 24, 1999 David (Texas, USA) Can you give me some information on rocks from the moon? The Apollo and Luna missions brought back 382 kg of rocks and soil back to Earth. These rocks, made of breccia, basalt and anorthosite, have told us a lot about the Moon. Even today, scientists are studying these rocks.
February 3, 1999 Shahab I was told that NASA done research and discovered a huge crack down the middle of the moon (or a split) is this true ? Well...I don't know of any huge cracks. But it does have a huge crater. The South Pole-Aitken is 2250 km across and 12 km deep. It is the largest impact crater in the solar system.
October 13, 1998 Gareth (Malaysia) I would like to know what mechanism is involved in the reflecting of lights from the moon's surface. We know light reflects from a shiny surface ( and of course,due to the fact of the critical angle and all ) However,the moon's surface is rough and is nowhere the material of a reflective materials. An object does not need to be shiny to reflect light. Everything you are able to see reflects light of some kind. White objects reflect a lot of light, while black objects absorb most of the light that hits them. The moon is simply, like every obje ct (rough or smooth or shiny), reflecting the light which hits it.
September 8, 1998 Lindsay (USA) What is the Moon made of? When you look up at the Moon, you are seeing a surface of rocks and dust. These rocks are sometimes called by special names like basalt or anorthosite, but they are really just old rocks!
July 15, 1998 Mark (California, USA) I really enjoy observing the moon with my 10' SCT. Has there ever been a 'new' feature observed on the moon's face from an impact of any kind, or have we just been looking at the same features all these years? Also, how large of an object would have to impact the moon's surface in order to see a new feature? As far as I know, no new features have been seen on the Moon since the Moon's features have been tracked (since Galileo's time). This makes sense seeing as there have been less and less cosmic collisions as the years go on. Most of the Moon's craters were probably formed over 3 billion years ago when there was more "junk" floating around in space. Since then, much of that junk has been coalesced into the larger bodies so there is just less "junk" floating around.

It is thought that the asteroid that entered the Earth's atmosphere, creating a 106 mile crater and killing off the dinosaurs, was about 6 miles in diameter. For you to be able to see an impact crater on the Moon with a small telescope or even binoculars, the crater would have to be about 30 miles in diameter. Even an asteroid (with an estimated diamter of 1km) would create an impact crater of greater than 30 miles in diameter.

May 4, 1998 Travis (Minnesota, U.S.A.) Does the discovery of ice on the moon mean that one day in the near future man will be able to colonize it? The discovery of ice doesn't mean we will be living on the moon very soon, but it makes it much more of a possibility, since water is essential to life. Since transporting things through space is very expensive, finding water on the moon means it wou ldn't have to be transported there, making living there a more reasonable possibility.
April 16, 1998 Shane (Perth, Western Australia) Say we find that the Moon's materials are a great source for building large 'starships' or even for construction materials on Earth!. What % (approx) of the moons mass would be 'safe' before we start to affect its orbit? Even if all the mass ever moved by man on Earth (such as lake creation/drainage) was removed from the Moon, there would be no noticable effect on the Moon's orbit except to astronomers who keep extremely accurate records. Also, chances are, the Moon and the crust of the Earth are made of the same material. (Current Moon-formation hypothesis says that a large body the size of Mars crashed into the molten Earth and made a big splash, which became the Moon.)
March 24, 1998 Jacqueline (Michigan, USA) What is the latest information regarding plate teconics and Mars? How about our moon? Since Mars is much smaller than Earth, the amount of heat inside is less. This limits tectonism. As a result, we do not see the plate tectonics that Earth has. The surface of Mars is just one large plate. Instead of plates, we see canyons and crate rs formed by rifting, erosion, and landslides.
The moon also is a single plate, deeply pitted and cratered.
January 12, 1998 Mallory (Missouri, USA) What would happen if you poured water on the Moon's surface? Most likely, if you poured water on the Moon's surface, it would disappear on you! You see the Moon has such a low pressure (because of its lack of atmosphere) that water would most likely vaporize so you couldn't see it. There is one case in which water might stick around on the Moon's surface: in a very dark crater where it is very, very cold! Here the water might remain on the Moon as ice.

Last modified April 19, 2002 by Jennifer Bergman.

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