Blow Up the Moon

[Spudo]

Hi, I was just wondering, would it be possible to totally explode the moon? I mean, would all of Earth’s nuclear weapons be enough to destroy it? Would a nuclear missle even explode in space? If one wouldn’t, what other methods of blowing up the moon would be available? Once the moon is destroyed, how would the lack of it effect Earth? Thanks

P.S. No, I’m not a loony

[CalMeacham]

Nowhere near enough. I don’t recall the figures, but it takes a LOT to blow up a moon or planet. American Journal of Physics ran a note on the energy required to blow up Alderaan back when Star Wars first came out, and it’s a sobering figure.

[Steve_Wright]

Oh, well…

To take them in order:-

Yes, if you could apply enough destructive energy, you could explode the moon.

No, all of Earth’s nuclear weapons would not be enough to provide anywhere near that amount of energy.

Yes, or at least I’m pretty sure, a nuclear missile would explode in space. Fission and fusion reactions don’t need oxygen; the only question is whether the conventional explosives used to trigger the initial reaction need oxygen, and I’m pretty sure they don’t.

Thermonuclear bombs are at the upper level of the destructiveness to which modern science has access. If they can’t do it, nothing we’ve got can.

I think the possible effects of the moon’s absence have been discussed before, you might want to do a search. However, even if you blew up the moon, you’d still have a lot of fragments, with the same total mass as the moon, moving in more or less the same orbit; this cloud of fragments would have pretty much the same effect on Earth as the moon (and, gravity being what it is, would pretty soon collapse back together to form a single body). To actually get rid of the moon, you’d have to hit it hard enough to send the fragments flying out of their orbit around the earth. Again, Space: 1999 notwithstanding, we are not in a position to deploy that amount of energy.

Just why do you want to explode the moon anyway? Wouldn’t writing your name on it with a giant laser be enough?

[Una_Persson]

Yes, nuclear weapons will quite happily explode in space, provided that the extreme cold does not damage their circuit boards and controls.

[Juan_Agudelo]

I am not a specialist, but I doubt very much that anything we can make would do much to the Moon. You can see on its surface that the comets and meteorites have tried plenty of times, and it is still there…

Besides, blowing up a body does not vanish the materials it is made of. A lot of it would fall into the Earth, threatening at least every life form. Some of it would fly away, maybe captured by the Sun or some other planets. I would guess that most of it would either reintegrate into a new Moon or orbit the Earth much like a ring (as Saturn’s) or a belt of asteriods.

[Sublight]

As for the effects of delunarizing the Earth, here’s Cecil’s take on the question.

[Phobos]

And some of the follow-up…
http://boards.straightdope.com/sdmb/showthread.php?threadid=44050
http://boards.straightdope.com/sdmb/showthread.php?threadid=44608

[Duck_Duck_Goose]

In the SD “Moon Go Boom” link from Phobos (the first one, above), the Bad Astronomer has a link to info, but by this time (a year later) it’s a Page Not Found.

originally posted by Bad Astronomer:
**Blow up the Moon? Not too soon!
Blowing up the Moon is literally impossible with our current nuclear arsenal. I have a description of what it takes to destroy a planet at http://www.badastronomy.com/wwwboard/messages/327.html.

Using numbers for the Moon (radius = 1738 km, mass=7.35x10^25 grams) I find that it takes about 30 trillion megatons (3x10^13) to blow the Moon up. Considering the largest bomb ever claimed to have been exploded was less than 100 megatons, we’re a bit short of the mark.

A collision with Eros could do it, but Eros would have to be moving incredibly fast, about 5000 kilometers/second, to give it enough energy to wipe out the Moon. That’s a good fraction of the speed of light. **

Yo, BA, can you look through your filing cabinets and find that?

Poking around for some numbers on the Web (strange, there don’t seem to be that many people out there working on how much it would take to blow up the moon)…

These folks were just trying to move an asteroid, but maybe some kindhearted math geek could extrapolate?

http://physicsweb.org/article/news/02/6/4

The researchers constructed a mathematical representation of the irregularly spaced near Earth asteroid Castalia for their calculations. They assumed it would be made of solid rock, a pair of solid rocks separated by rubble, or a 50% porous agglomeration of large boulders.

To simulate a collision they imagined a 8m diameter basalt sphere travelling at 5 kms-1 hitting the asteroid. This would impart a explosive force equivalent to a 17 kiloton nuclear device. They found that in most cases only 10 percent of the asteroid’s mass reached escape velocity, the rest of the material stayed loosely bound in the area. A hard rock object on the otherhand was more likely to simply split into two.

http://physicsweb.org/article/news/02/6/4/1/news-2-22-4-1

The impact basalt sphere weighs 6000 tons compared with over 1 billion tons for Castalia.

http://nssdc.gsfc.nasa.gov/planetary/factsheet/moonfact.html

Mass 10[sup]24[/sup] kg x 0.07349

So if Castalia was a billion tons, and the moon is 0.07349 x 10[sup]24[/sup] kilograms, and it took a 17 kiloton nuke to bust up Castalia a little, how much would it take to bust up the Moon a little?

Class?
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
…Anybody?

[bell rings]
[stampede for thread exit]

[Ike_Witt]

You can always try to carve your name into the moon with a big ass laser.