this may have been touched upon before and i do apologise if it has as this is my first post you see. Now, aside from phil plait probably being a CIA sponsered de-bunker[thats a joke, but i wouldnt put it past them] surely the sand is so fine due to the moons gravity, foot prints or tyre marks, cant actualy leave a print. again i apologise if this is a re-stated question but could some one please explain how they got there?,always been a query of mine.

__________________
2012

Is that the only user name you could come up with???

The dust on the surface of the Moon is very fine grained, almost like a powder. At least, that's how Neil Armstrong described it.

You'll find that talcum powder will hold a print, even though it's dry. It's a side effect of powders.

As for the BA being a CIA sponsored debunker, even if it's a joke, why would they bother? If he's being paid to tell lies, it shouldn't be hard to prove him wrong. And if he's being paid to tell the truth, well, why would you pay him?

And welcome to the BABB, though I must say you've got an, er, interesting name...!

what as apposed to R.A.F?. OK Mr.Royal Air Force. Though as to my name well essentialy theres a lot of truth in there isnt it, we are[and i am white u know] after all the greastest vermin/plague on the planet. Hoho, and i hope theres no one stupid enough to take it seriously or my comment for that and drag it into some non-sequencial sociological flame war please.

Yes but u see very fine powder yes ok ON EARTH, but u see thats still affected by gravity isnt it, the moons gravity would leave no such foot print even if u jumped constantly up and down on any fine powder it just wouldnt leave a mark. And the finer it is the less of a print is made, so what he says makes no sense.

__________________
2012

Wow...how offensive! Are names like that even allowed?

__________________
An open mind is like an open window...without a good screen you'll get all sorts of weird bugs!

Actually, R.A.F. are my initals.

Somehow, I think that the BA will "take it" very seriously.

An astronaut plus space suit weighs about 150 kilograms on Earth. The Moon's gravity is about 1/6 of the Earth's. Therefore, on the Moon, an astronauts weighs about 25 kilograms.

The astronauts' boots would be very roughly 40cm x 15cm each, for a total surface area of about 1200 square centimetres. This equates to a pressure of about 20 grams per square centimetre.

That's certainly enough pressure to leave an imprint in powder.

There's also footage of the astronauts kicking powder. Presumably the act of kicking will leave an imprint in the surface.

What sort of pressure would you consider necessary to leave an imprint?

I agree.

I wouldn't think so, but I've PMed the BA...it's his board, and his decision.

the moons gravity would leave no such foot print even if u jumped constantly up and down on any fine powder it just wouldnt leave a mark.

Why do you say that?

And the finer it is the less of a print is made, so what he says makes no sense.

Why do you say that?

__________________
"Facts are stubborn things." --John Adams
Clavius Moon Base

Jump up and down on a pile of rocks. Then jump up and down on a pile of baby powder. In which pile did you leave prints?

__________________
"I'm making wheatloaf. It's like meatloaf, only with wheat"
"Isn't that just...bread?"

I imagine he doesn't bake much. Flour and the even finer, confectioner's sugar, is very easy to mold when compacted. Dump a bag on your counter and make a handprint. If there's only an 1/8 of an inch thick of flour the print is vague, if there's an inch or two, the print is very recognizable. And how deep is lunar topsoil? Now if you keep pounding your hand on the layer of flour on your counter (simulating jumping), you're going to get a mess of handprints that may lose their preciseness (the shape of your hand), but prints will remain as you continue compacting the flour. An even finer powder, loose translucent powder that women use on their faces, still shows a print of the lines on my finger at 3/4 inch. Much of that kind of fine powder is displaced to the side. The moon's powder isn't even that fine.

This is easily seen with turtle tracks on the beach in FL. The turtle tracks remain there all day until rain, strong winds or beachrakers alter them. But there is no wind or rain on the moon and Peter B explained the pressure of an astronaut's jump. I'm not sure what the lunar "powder" is best compared to on earth. One astronaut said it was like powdered snow...powder is so vague.


(BTW, I was watched some of the lunar walks again last night. I believe it was on Apollo 15 where the astronaut was tripping over a rock like a clutz. I thought, now if that was fake, that would be an odd moment to film. Ditto for when the astronaut throws something and loses control and falls down. Their movements don't have the look of anything I've ever seen on film. Someone correct me if I'm wrong).

__________________
The perception of the comic is a tie of sympathy with other men, a pledge of sanity. We must learn by laughter as well as by tears and terror. ~ R. W. Emerson

I imagine he doesn't bake much.

Or mix concrete.

I'm not sure what the lunar "powder" is best compared to on earth.

Portland cement has been suggested, as has coal ash.

__________________
"Facts are stubborn things." --John Adams
Clavius Moon Base

OK, let me get this straight, because 1/6 of earth's gravity doesn't really mean anything to me without being able to correlate it to something on earth.

On Clavius I read this:
In the Apollo 15 film when the astronaut trips over the rock, his left foot kicks soil that looks like as if threw a two-cup container of flour in a horizontal trajectory. At the same time a "dust cloud" goes up and away and floats off the side of the screen. I don't see how coal ash being kicked on earth would show the same easily seen "dust cloud" if there was no wind to uplift it. Even as I squeezed my vacuum cleaner bag, which was chock full of dust, the cloud goes up, but doesn't float up AND sideways indoors like it does in that particular scene of the Apollo 15 film. (This is probably dumb question of the day).

How would hoaxster's simulate that scene on a set?

(I am not familiar with Portland cement).

__________________
The perception of the comic is a tie of sympathy with other men, a pledge of sanity. We must learn by laughter as well as by tears and terror. ~ R. W. Emerson

Portland cement is the gray powder mixed with sand and water to make common concrete.

It's very difficult to keep particulates from aerosolizing, as anyone who works with Portland cement can tell you. It's fairly easy to sift particles to make sure there aren't any larger than a certain size, but it's much more difficult to keep particles smaller than a certain size out. So if you have a truckload of particulate that you're going to dump onto a set to make it look like sand, you're going to get dust.

At my theater, where 1776 is now playing, we previously staged South Pacific. We covered the stage with several hundred pounds of actual beach sand. After the cast and ground it up with their boots -- and tracked it all over backstage -- the dance numbers would raise clouds of dust. So before each performance we had to run the rain sprinklers for a few seconds.

__________________
"Facts are stubborn things." --John Adams
Clavius Moon Base

Do you guys have mods here?

Or does BA have to clean up everything?

P.S. If you don't ahve mods here, this is an example of why you should. The sooner, the better.

__________________
Then you will know the truth, and the truth will set you free.

- Jesus -

Oh, I know what dry cement is, I just don't hear the Portland part of it. But great, now I know there are about eight types of Portland cement for different usages.

I still can't see how that would produce the dust cloud as in the Apollo 15 film scene I'm speaking of. That dust cloud goes high and moves like smoke(like the smoke from fireworks) from the action of one spaceboot. It doesn't seem like that could be simulated on earth. I guess I need to read more about how dust "floats" in a no-air, 1/6 of earth's gravity environment.


And Junkyardfrog, I believe the BA has done something about KKKTWM. It is a crass nic.

__________________
The perception of the comic is a tie of sympathy with other men, a pledge of sanity. We must learn by laughter as well as by tears and terror. ~ R. W. Emerson

Please explain. Why would low gravity create fine sand? Why do you say "sand"? Why do you think fine grain "sand" can't make prints?

1. You can leave a very nice fingerprint in dust on any surface, including a wall or ceiling as well as a tabletop. That's "with", "perpendicular to", and "opposite" the gravitational vector.

2. As has been explained, there's plenty of force to make an imprint in the powder on the lunar surface.
2a. As was also explained, it's a powder, not "sand".

3. The finer it is, the more of a print is made. Fine powder sticks together quite readily when compacted. Maybe you're getting tripped up by thinking about relatively coarse sand, which needs some moisture to take a print well.

Hmmm, tell me, Kill, Kill etc. would it offend you if I changed my name to Hang-Mike-Moore-who-is-not-God-and-all-his-terror-loving-doper-seditionist-fans? How about a-bullet-a-day-keeps-the-peace-nazis-away?

I don't understand why that username hasn't been deleted yet.

__________________
Then you will know the truth, and the truth will set you free.

- Jesus -