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How NASA Will Bomb the Moon To Find Water
Posted by
kdawson
on Fri Aug 15, 2008 10:46 AM
from the black-eye-on-green-cheese dept.
from the black-eye-on-green-cheese dept.
mattnyc99 writes "A few weeks ago we got first word of NASA's plan to crash a spacecraft into the moon next February. The new issue of Popular Mechanics has an in-depth look at the Lunar Crater Observation and Sensing Satellite and its low-cost, lightning-fast mission prep — even if delays have pushed it to late February or early March. Quoting: 'Andrews had no budget for an expensive lander to seek water, and conditions in the eternally dark polar craters would kill rovers, with temperatures close to minus 300 F. Instead, Blue Ice and its partners at Northrop Grumman came up with a concept to bring the lunar floor out in the open.... Since engineering precision hardware would break the budget, the LCROSS team had to make existing components work together.'"
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NASA Plans to Smash Spacecraft into the Moon 176 comments
djasbestos writes "NASA is planning to smash a spacecraft into the Moon in order to look for hydrogen deposits in the poles. More notably, it will impact with significantly greater force (100x, per the article) than previous Moon collisions, such as by the Lunar Prospector and Smart-1 probes. Admiral Ackbar was unreachable for comment as to the exact location and size of the Moon's thermal exhaust port."
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Bomb what? (Score:5, Funny)
Re:Bomb what? (Score:5, Funny)
I'm still waiting for them to rename that planet to Urectum to stop the stupid jokes.
Parent
Re: (Score:3, Funny)
Udamnnearkilledum would also be acceptable.
percussion engineering! (Score:5, Funny)
I hit stuff to fix it all the time, why shouldn't they?
Re: (Score:2)
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Re:percussion engineering! (Score:4, Funny)
"Percussive maintenance"
Parent
That Old Mr. Show bit (Score:5, Funny)
"The United States can, should, and will BLOW UP THE MOON!"
http://www.youtube.com/watch?v=kHpX5aa5Lz4 [youtube.com]
First a satelite... (Score:2)
Premptive Strike! (Score:2)
See http://www.ironsky.net/site/ [ironsky.net] for details...
Bombing the Moon for water? (Score:5, Funny)
And I find the 'water' reason to be pretty transparent. We all know that there's oil up there and this is yet another neo-con plan that's going to suck us into another war to boost Bush's ratings. But when images of those poor Amazon women up there start coming back, it's jut going to blowup in their faces like Iraq did, and further depress our economy.
Crash Test Dummies (Score:2)
Where won't they go next!
Fahrenheit? (Score:2, Funny)
temperatures close to minus 300 F
1850 called. They want their unit of measure back.
Re:Fahrenheit? (Score:5, Interesting)
You know, while I'm generally in favor of the metric system over imperial, I've never cared nearly so much about the Celsius v. Fahrenheit debate.
Fahrenheit makes more sense in day to day contexts. 0 is very cold, 100 is very hot (both from a human experience point of view), and you have more precision on the temperatures in between. Now in this particular case it's so cold that it doesn't really matter; if I told you it was -184 C, or -300 F it wouldn't really change the fact that you can't conceive of the temperature as anything but "really, really cold".
Besides, who are you trying to chastise? The temperature was given in a quote from the article. Would you prefer Slashdot editors mangle quotes to conform to your prejudices?
Parent
Re: (Score:3, Insightful)
It only makes sense because you're used to it.
In Celsius 0 is also very cold, but at the same time more meaningfull ("what will happen to water today?" or "what can fall from the sky today?"). Same with 100, also very hot, and usefull even in the kitchen. (and both 0 and 100 can be easily calibrated on Earth). And no, 100 Fahrenheit isn't very usefull medically - it's a temperature of somebody with severe fewer; if it would be "normal"/"border one" - I would agree with that one.
As for precision - BS, even C
Re:Fahrenheit? (Score:5, Insightful)
"what will happen to water today?"
Before or after the salt trucks come through?
"what can fall from the sky today?"
Because it's not possible for different layers of air to be at different temperatures?
"Same with 100, also very hot, and usefull even in the kitchen."
No, it's not. When was the last time you stuck a thermometer into a liquid on the stove in the process of cooking? Does your range have temperatures on the burner controls? Boiling water isn't useful in the kitchen because it's "exactly 100 degrees Celsius" (which it isn't), but because it's at a constant temperature, regardless of what number you chose to associate with it. And even then, stovetop recipes have to be adjusted for altitude ("How high am I above sea level?" is a question asked more often than "What temperature is this boiling water?")
"(and both 0 and 100 can be easily calibrated on Earth)"
No, they can't. Celsius is defined as a linear offset to kelvin, period. At a "standard" atmospheric pressure of 101 325 Pa, water boils at about 99.974 C (and this is a mathematical approximation [iapws.org] based on experimental data). So even if you had a barometer that was accurate to 1 Pa absolute, arbitrarily declaring the saturation temperature in the room at the time as "100 C" is no more accurate than declaring it to be "212 F" (and at least there the approximately 180 F temperature difference between freezing and boiling is easier to subdivide geometrically).
As a linear offset to thermodynamic temperature, no mere mortal has the equipment to properly calibrate their thermometer (Celsius or Fahrenheit) in their kitchen.
"And no, 100 Fahrenheit isn't very usefull medically - it's a temperature of somebody with severe fewer;"
With respect to measuring human body temperature, Fahrenheit is useful medically by simple virtue of being more granular. Assuming a normal body temperature of 98.6 F (37 C), a fever of 100 F is still less than 1 C above normal. 38 C is 100.4 F.
"BS, even Celsius scale has way more precision than we need in day-to-day life"
Then the adjustments on your thermostat are marked only to the nearest 5 C? If it's more granular than you need, then put your money where your mouth is and set your thermostat up another 2 C.
"it's just above zero", "it's around 5", "a bit below 10"
So the "metric" temperature scale is one that people "feel" in units of 5 rather than 10? In Fahrenheit, that would be "in the 30's," "in the 40's" and "in the 50's," respectively.
Parent
Re: (Score:3, Informative)
I'm not sure if you're being sarcastic, but Fahrenheit is a decimal system based around the temperatures of water freezing and boiling at a very specific atmospheric pressure. 32F is defined to be the temperature at which water freezes and 212F is defined to be the temperature at which water boils. It's exactly the same thing as Celsius except for where the two points are placed.
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Risk of retaliation (Score:5, Funny)
The good news is that the Loonies can't do anything about it. I mean, all they could do is throw rocks at us, and what good would that do?
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He'll be lucky if he can get a packet out, let alone get those rocks in the catapult on target.
TANSTAAFL!
sounds like a warped 60s slogan (Score:2, Funny)
"stop the nukes"
"yeah yeah right on!"
"save the whales"
"you got that right brother!"
"bomb the moon"
"right... i mean, what?"
"bomb the moon with love, man"
"oh right, right, bomb the moon with love!"
"nuke the whales"
"ummm..."
This is Awesome (Score:5, Insightful)
Somehow, this mission strikes me as one of the coolest things NASA's done in a while. It's a struggling unit of the organization, working with spare parts from scrapped projects, jury-rigging a satellite together that will tow the spent upper stage of a rocket to the moon and smash the chunk of metal otherwise slated to be space debris into the closest heavenly body to send an Earth-visible (with a decent telescope) plume from one of its poles. Finally, it will analyze the plume to figure out if there's ice there.
Totally. Awesome
Tricky shot (Score:3, Funny)
Apparently to make this work NASA will have to hit the opening of a thermal vent that's less than 2 meters across at the end of a canyon lined with defensive gun placements.
Many NASAians died getting us this information.
Re: (Score:3, Informative)
Well all mass exerts a gravitational pull on all mass, so yes they affect each other.
Are you afraid this will affect the Earth's orbit around the Sun? The change will be negligible --- the energy we'd need to mess up the orbits dangerously is far beyond us.
Re:Earth's Orbit? (Score:5, Informative)
I though it was well within our current power to fuck up the Earth's orbit. Given that the whole time I was growing up we were constantly told we could "blow up the Earth 20 gazillion times over" I was under the impression that we could fairly easily knock it off kilter.
When people say we could blow up the entire Earth, they really mean we could cover the surface of the Earth in nuclear explosions. It would kill all of us, but the Earth wouldn't care. It would just keep trundling along as ever.
Some maths: Suppose we wanted to increase the speed of the Earth by 1m/s. Kinetic energy = mass * speed^2, so (as the mass of the Earth is 5.9736*10^24 kg) we'd need 5.9736*10^24 joules. A megaton explosion is 4.184*10^15 J, so we'd need the equivalent of about a billion megatonnes of TNT. That's about one hundred million pretty big nukes (assuming all the energy of the nukes goes into the Earth's movement, which it wouldn't). And that's just to accelerate the Earth by 1m/s. And when you add to that the fact that the Earth's orbit is stable (so we need a lot of movement to do any real damage), you can see how little we could really do.
Hope that makes sense!
Parent
Re: (Score:3, Interesting)
Your computation actually has some errors in it. The amount of energy required to increase the earth's speed from what it is (about 30,000 m/s) by 1 m/s is not the same as the amount of enery needed to increase it from 0 to 1 m/s (which is what you computed, except that you also made a mistake by a factor of 2).
A better estimate (with same mass, but increasing the speed from 30,000 m/s to 30,001 m/s) yields
1.7921e29 joules needed. That's 5 orders of magnitude greater than your solution.
I once computed that
Re: (Score:3, Informative)
Even if we could blow up the Earth several times over (we can't), doing that requires orders of magnitude less energy than actually changing the Earth's orbit. If you blow up the Earth into millions of tiny little chunks, all those tiny little chunks will keep happily orbiting the sun (See: Asteroid belt) at very nearly the current speed and path that the Earth currently travels.
An object with the mass of the Earth, travelling through space at the speed that it is, has an unbelievable amount of kinetic ener
Re:Earth's Orbit? (Score:5, Informative)
Parent
Re:Earth's Orbit? (Score:5, Funny)
Parent
Re:Earth's Orbit? (Score:5, Informative)
The mass of the moon is ~ 7e1022 kg
I think you're mixing up 7x10^22 and 7e22 there; the Moon's mass most certainly is not 7e1022 kg. Estimates for the mass of the observable universe, for example, are around 2e52 kg [wikipedia.org].
That said I agree with your point - this will have an utterly negligible affect on the orbital dynamics of the Moon.
Parent
Re:Earth's Orbit? (Score:4, Insightful)
Virtually all of the mass of this mission, except for maybe a little rocket propellant, will stay within the Earth-Moon system, so the center of gravity of the two won't change. In other words, no, this won't affect Earth's Orbit thanks to CONSERVATION OF MOMENTUM!!
Parent
Re: (Score:3, Interesting)
Earth did have a second moon (first moon?).
http://www.space.com/scienceastronomy/solarsystem/second_moon_991029.html [space.com]
It grew up and moved out. Now it just visits once in a while.
Re:Earth's Orbit? (Score:5, Funny)
> Isn't Earth's orbit intimately mingled with it's moon?? How precise can the potential impact be measured in relation to this fact? I think Earth's orbit is fine where it is...
Sigh. I blame public schooling.
Parent
Re: (Score:2, Informative)
The moon is smacked by meteors all the time, many much larger than any space probe could ever be. After all, it has a nasty case of acne scars. Most meteors are still usually too small to make any detectable difference. It's probably been hit by some biggies that perhaps could alter its orbit, but the average
Re:is that a good idea? (Score:5, Insightful)
Simple physics tells us that bombing it with any bomb we currently have or are likely to have in the forseeable future will make no measurable difference and probablly a lot less difference than the various natural rocks that have hit the moon over the centuries.
Parent
Re:is that a good idea? (Score:5, Informative)
Granite contains Uranium. Get a geiger counter and test the nearest granite countertop and be amazed!
Of course, it's not *dangerous*, but it is definitely radioactive.
Parent
Re:is that a good idea? (Score:4, Informative)
Most of the radioactivity in stone and ceramic building materials is from potassium 40 decay, not uranium.
Parent
Re: (Score:3)
Where is the "Whatcouldpossiblygowrong" tag? If this article had ANYTHING to do with biology, it would have been up already.
Re:The Time Machine (Score:5, Funny)
Geez, a plot like that'd make me crack the DVD in half and eat it.
Parent
Re: (Score:3, Interesting)
That is what I was thinking.
I heard a conspiracy theory that the renewed interest in the moon by NASA at the direction of George Bush was due to the discovery of Helium-3 there.
Helium-3 is a non-radioactive isotope http://en.wikipedia.org/wiki/Helium-3 [wikipedia.org]
My understanding of this is that this means is you can have fusion without radiation only dealing with heat and actually raw electricity as a by product. So it seems the energy generation is far greater than other forms of fusion. ... Or in other words.. Bush
Re:Wasn't this the plot of that Time Machine Remak (Score:4, Insightful)
My God. Has the IQ of Slashdot dropped twenty points in the last fifteen minutes?
Parent
Re:Wasn't this the plot of that Time Machine Remak (Score:5, Funny)
It's a bit hard to tell but I'm afraid you're on to something. We seem to be getting more "whoosh" posts before the joke.
Parent
Re: (Score:2)
Seriously. I saw an AC make the same comment first. I wrote it off as a troll attempt. Then I see three logged in users making the same point. I was about to make a reasoned retort, but couldn't get past the "How Fricking Stupid Do You Have to Be!?!?" shock. Very similar when I have to explain something technical to the COO.
Re:Wasn't this the plot of that Time Machine Remak (Score:4, Funny)
Look up gravity on the internet, if you don't believe me. I don't like the idea of loosing the moon just for sake of an experiment.
Parent
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P.S. It's "lose", not "loose". And that's why I never even considered a career teaching English in college.
Re: (Score:2)
His post was a joke. Totally a joke.
And, technically, his use of "loosing" works in the sentence. It is certainly not what he intended, but it also works in a bizarre, funny way.
Re: (Score:2, Funny)
Re:Have they exceeded their authority? (Score:5, Insightful)
If you are indeed worried about this, perhaps a remedial course in physics is in order. You might start a couple of books before the ones on orbital mechanics.
If you're funn'in us - well, sorry - not quite enough caffeine here.
Parent
Re: (Score:3, Funny)
"He wasn't an astronaut! He was a TV comedian. And he was just using space travel as a metaphor for beating his wife."