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Which Of These Obejcts Are Useless On The Moon Surface?


jeosar

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Hi there jeosar, well a ball point pen is not much good lack of pressure, same problem as being in space. The box of juice would be very hard to drink and you'd probarbly suffocate trying to drink it, but again lack of air pressure makes it useless. Football pump again useless because of the lack of atmosphere and lack of air pressure issues. Flashlight should hopefully actually be useful. Matches useless, lack of oxygen to make them be able to burn. Pencil unlike the pen would be useful, the russians used them in their space program for the cosmonauts, rather than spending the $10 million to create a pressurised pen. An alarm clock may be fine to tell the time, but the alarm function is useless as not enough atmosphere to carry the sound waves. Finally the juice jug would be useless as the reduced gravity would mean liquid would to easily come out.

 

Hope this helps. :)

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Hi jeosar and Ascended, and welcome to hypography! :) Nice to see some new folks.

 

These are some pretty fun “what if this were on the moon?” questions. Since Ascended has already started, I’ll respond to his answers:

 

... well a ball point pen is not much good lack of pressure, same problem as being in space.

The reason ordinary ball point pens (compare to pressurized “space pens”) don’t work in space is not lack of outside air pressure, but lack of gravitational force on the ink in them. There is gravitational force on objects on the Moon’s surface, tough only about 1/6th that on Earth’s, so an ordinary ballpoint pen that would work held very tilted (within about 10o of horizontal) on Earth would work on the Moon.

 

Temperature could be a problem, as eventually the ink in even a pressurized space pen will lose enough heat to become too thick to flow (or even freeze entirely), I think it would take a while for that to happen. As there’s not much gas to convect heat, as long as you kept you pen off of cold surfaces in the shadows, I don’t think this would be a problem. The opposite – the ink boiling, or the pen melting – might be a problem if you left it in the bright sun lunar sun, as the Moon’s insulating near-vacuum wouldn’t allow it to release much heat.

 

The box of juice would be very hard to drink and you'd probarbly suffocate trying to drink it, but again lack of air pressure makes it useless.

Yeah, cracking the ‘ole space helmet for a sip of juice is some pretty unwise astronaut behavior, but provided you’re careful to avoid letting the juice in it freeze (same as with the pen above), squirting it out in the usual way shouldn’t be a problem – though once out, it will boil and/or freeze quickly, depending on conditions.

 

Though liquids like juice aren’t compressible, there’s a little air in a juicebox, so there’d actually be an initial pressure difference of 1 atmosphere between its inside and out, at least some of the juice should be ejected under pressure when you stab the straw through the little foil hole in the box.

 

Football pump again useless because of the lack of atmosphere and lack of air pressure issues.

Agreed – an air pump isn’t likely to be of much use in an airless environment.

 

Flashlight should hopefully actually be useful.

Agreed – though you might have to be carefully with a really powerful one, since ordinary batteries produce heat when discharging, and in vacuum, it’s hard to get rid of heat, which could lead to destructive overheating. Low-power electrics cope via radiators, but some thoughtful engineering can be needed for light-power ones. The big motor-powering batteries on the Apollo Lunar Rovers had a cunning system on them that involved covering them in wax which melted when the Rover was running, which was then uncovered, dusted off, and allowed to cool and harden while it wasn’t.

 

Matches useless, lack of oxygen to make them be able to burn.

A typical modern match gets the oxygen it needs for it’s initial burn mostly from potassium chlorate (KClO3), so a match would burn briefly on the surface of Moon’s surface. So, if you happened to have something that would burn in a vacuum to set afire – say a heap of solid rocket fuel (or of match heads), a match could be useful. The usual cigarettes and campfires aren’t possible, so I’d term matches on the Moon “marginally useful”.

 

Pencil unlike the pen would be useful, the russians used them in their space program for the cosmonauts, rather than spending the $10 million to create a pressurised pen.

:Exclamati This is actually a myth (see this Snopes article and this wikipedia section).

 

Fisher developed its famous pressurized pens with their own money, selling several hundred to NASA in 1965 at the less than the price they’d sell for a few years later in the Cape Kennedy visitors center gift shops, while the USSR space program bough 100 Space Pens and 1000 ink cartridges for them in 1969. Before these dates, NASA astronauts used pencils in space, which they didn’t much like doing because of the risk of floating broken leads and fires (pre Apollo 1 disaster manned spacecraft had 100% oxygen atmospheres, so even as small a combustible as a wood pencil was a serious concern). By some accounts, before getting Space Pens, USSR cosmonauts also used lead-filled wood pencils in space, though by others, they used only grease pencils (crayons of sort).

 

The conventional wisdom is that everybody got a good deal out of Fisher’s Space Pen: Fisher got some high-profile advertising and endorsements; NASA and the USSR’s space agency got good pens; while waves of visitors (including me as a child) got some nice space souvenirs.

 

Fisher’s self-histories state it spent over $1,000,000 developing ball point pens in general, but to the best of my knowledge, only a fraction of that was spent on upgrading their ball point pen cartridge to the pressurized one used in the space pen. Putting some ink in a tube with pressurized at one end and a good quality ball point on one end, while clever, isn’t a huge feat of engineering.

 

An alarm clock may be fine to tell the time, but the alarm function is useless as not enough atmosphere to carry the sound waves.

Completely agree.

 

Finally the juice jug would be useless as the reduced gravity would mean liquid would to easily come out.

Agreed, plus at zero atmospheric pressure, water is either a solid or a gas, making jugs for holding it useless no matter how careful you are about not sloshing and spilling.

 

You could argue that a juice jug would make a pretty good scoop for Moon dust and the like, but it’s not really a juice jug then.

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i think everyone is being way too negative here. there is a good use for each and every one of those items on the moon.

 

the ballpoint pen could be used to mark an interesting sample by sticking it in the ground, for example. as someone has pointed out the juice jug could make a decent scoop. a flashlight would be ideal for exploring deeper craters and even for taking a peek at the dark side as well as for signaling your colleagues or testing high power optics from earth. the matches would be ideal for propping open tired eyelids after long hours of exploring. the alarm clock doesn't need to use the alarm and can just be used for normal timekeeping, although if its a digital one it might have a vibrate function. this could be used either as a haptic alarm or for carrying out micro-seismic experiments.

 

at the very least, if you had all these objects on the moon you could do all sorts of interesting variations of david scott's famous demonstration of what happens when you drop a feather and a hammer at the same time on the moon.

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Ballpoint pen, matches, alram clock are useless in the moon. There is no gravity in the moon, so the ball point pen will not write. Burning means reaction of carbon in a object with oxygen. There is no oxygen in the moon, so matches won't work. Sound can't travel in vacuum. A moon is a big vacuum. So alram clock won't work.

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Ballpoint pen, matches, alram clock are useless in the moon. There is no gravity in the moon, so the ball point pen will not write. Burning means reaction of carbon in a object with oxygen. There is no oxygen in the moon, so matches won't work. Sound can't travel in vacuum. A moon is a big vacuum. So alram clock won't work.

 

 

yes hellboy, there is gravity on the moon and while i'm not sure what use they would be matches will indeed burn in a vacuum, they have their own oxidizer, google is your friend dude...

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Ballpoint pen, matches, alram clock are useless in the moon. There is no gravity in the moon, so the ball point pen will not write. Burning means reaction of carbon in a object with oxygen. There is no oxygen in the moon, so matches won't work. Sound can't travel in vacuum. A moon is a big vacuum. So alram clock won't work.

 

Don't trash up the board with such nonsense and read the previous posts before posting anything.

The Moon does have gravity and a pen would work (if not frozen), a match would light on the Moon but not continue to burn (the match-head has oxygen compounds), and the clock would tell time whether you hear the alarm or not.

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EVERYTHING mentioned in the OP is useful. If I found any of that stuff on the moon I will immediately gather all of them into a sealed museum display case of weird **** found on the moon and charge people entrance money to come take a look at it. So you can turn strange moon rubbish into cold, hard cash. Awesome. Don't dis trash. Especially moon trash.

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