Hmm, I wonder if the poles would get hit less often than the tropics due to the distribution of asteroids being more or less in the ecliptic, or whether that's not sufficiently significant. Probably not -- I don't know of any latitude-dependent distribution of lunar craters.

LOL - I know that... I mean well I look at them from line of sight (on a mountain) only 30 miles away they're little specs...

Seville in the 16th century is the best example of what might happen. Spain got hold of the equivalent of a gold-filled asteroid - South America. All the gold and silver came in through the port at Seville, which became very rich, and inflation slowly radiated out from there to the rest of Europe.

Presumably people would start using gold for all sorts of other things -- eg. replacing copper in wires -- so the market would also expand.

The way you describe that perfrectly fots in with my idea that a 'caught' asteroid in orbit is worth more as a weapon system than as a gold mine. "Park it up there and drop pieces of it when you need some penetrating power"

Asteroids don't have tails.

I work at NASA, supporting the person who wrote the codes that is now used for planetary dynamics simulation, like this. It is an extraordinarily complex problem, and a specialized academic discipline in its own right.

n-body dynamics is a complicated, chaotic system. Getting any precision at all over any reasonable period of time is a feat of itself.

Not entirely trivial. Because it is chaotic, it's not terribly well behaved. People who try to integrate the solar system forward in time have to put some effort into accuracy, and ultimately accuracy is limited by our limited knowledge of the initial state of the system.

"or reply as to why are you down voting?"

well i don't want to get upvotes but if you disagree with me then please take some more time to write a quick comment as to why.

Well i posted asking if it will be visible to naked eye, someone quoted a part of the story (indirectly) saying that it won't be and i happened to have missed that part, and i get down voted (for missing reading a part of the story).. well then i acknowledge that i missed it and i get down voted still even then i asked the down voter why was he is down voting my comments and guess what.. i got down voted.. again. but no one has balls to write back, or maybe they are super busy with their work but anyways, and i wont edit this comment but i can say two things:

- you (or any of the downvoters) probably won't reply to this comment either. - this comment will (almost certainly) be down voted too.

lets see how correct i am..

The sad part is that regardless of whether it's copper or gold, the economics of mining asteroids still doesn't work out.

Gold is an industrial metal, though

...except that the solar system is two dimensional, aligned on a plane?

hmm well yes.. i almost forgot about the third dimension but that was a hypothetical situation after all.. :)

I'm pretty sure that said hypothetical impact can't exist. The object either has far too little energy to significantly change its orbit, or alternatively has enough energy but there is nothing moon-like left after that collision.

The moon has a mass of 7.349×10²² kg. Its mean orbital velocity is 1023m/s. So, with a perfectly-aligned impact, and perfect efficiency, to add velocity, you'd need to add energy equal to difference in kinetic energy. For 1m/s, that'd be 10²⁵J (assuming the change in mass is negligible). That's an incredible amount of energy, about 20 times greater than the Chicxulub impact (believed to have triggered the mass extinctions at the K-T boundary).

That's 1 m/s. You need far more than that. Earth escape velocity is 11200m/s. So, that would seem to need 10³⁰ J. And an impact would deliver that in well under a minute. Which would be a problem, since that's an order of magnitude greater than the gravitational binding energy of the moon.

Conclusion: impact required would fully obliterate moon.

(Moon mass and velocity, and escape velocity from http://nssdc.gsfc.nasa.gov/planetary/factsheet/moonfact.html. Gravitational binding energy and estimate of Chicxulub from Wolfram Alpha)

well moon moving out of its trajectory means alot more than tides (which in itself is pretty darn serious) IMO. The nights would be absolutely dark, also earth's rotation speed (AFAIK) is also affected by moon's gravity and bulges in both earth and moon's softer crust. Plus maybe we can adapt to such changes but our culture will change and it will be alot more difficult to live through that, imagine explaining to your kids/grandchildren what moon is (or rather was) and how it looked when it was closer/farther.

PS if moon gets a major hit, its highly unlikely earth stays 'physically' unaffected. The aftermath of the collision would leave numerous chunks of huge rocks in earth's near space and it would be almost certain that some of then then hit earth. And the effect of decent sized rock hitting the planet is better known to our long lost friends, the dinosaurs :)

An asteroid that could move the moon would have to be moving insanely fast, or be close to the size of the moon (due to conservation of momentum).

You get downvoted when your comments are low quality and/or don't add to the discussion. Every comment you write with "why did you downvote me???" is both low quality and doesn't add to the discussion.

Relax, it's only HN. Go build something instead.