# giant rocks falling from the sky? **URL:** \ **Category:** Factual Questions\ **Created:** [January 17, 2011, 1:13am UTC](https://boards.straightdope.com/t/giant-rocks-falling-from-the-sky/567888 "2011-01-17T01:13:33Z")\ **Posts on this page:** 20\ **Page:** 3
**Author:** ![msmith537](https://avatars.discourse-cdn.com/v4/letter/m/d9b06d/32.png) [@msmith537](https://boards.straightdope.com/u/msmith537)\ **Post date:** [January 17, 2011, 5:22pm UTC](https://boards.straightdope.com/t/giant-rocks-falling-from-the-sky/567888/41 "2011-01-17T17:22:10Z")
> [@meldiocre](#): > > so i just saw ‘deep impact’ about 13 years late, and i thought it was tremendous. emotional performances, pretty good effects, the works. then i got to thinking hey, instead of blowing up the giant rock of doom, why not just dig a hole roughly the size of the meteor (new york-ish) and line it with something indestructible so there’s no way a bunch of dust and whatever else will block out the sun and kill the world? > > if they can “mine all the fissile materials on earth” for a bomb in ‘sunshine,’ certainly they can make some kind of unobtainium cradle for a meteor? unfortunately everyone made fun of me for this idea, and then sent me here to ask you folks why it wouldn’t work. > > so my question is twofold: why wouldn’t it work, This is what we in the business refer to as a “dumb idea”. That is to say, nearly every part of it demonstrates a lack of understanding of physics that is so complete, one does not no where to begin to try to explain why it would not work. The short answer, it wouldn’t work for the same reason a Zippo lighter won’t actually protect you from a .357 Magnum fired point blank into your jacket pocket. The object is traveling so fast that it will simply blast through whatever is in its way as if that object did not exist. As a reference, [Meteor Crater in AZ](http://en.wikipedia.org/wiki/Meteor_Crater) is about 2/3 of a mile in diameter and was likely formed from an object about half the size of a football field traveling 12-20 miles per second. > [@meldiocre](#): > > and what WOULD we do in the event of a giant rock falling from the sky about to kill us all? Mostly vaporize. ---
**Author:** ![Dag\_Otto](https://avatars.discourse-cdn.com/v4/letter/d/439d5e/32.png) [@Dag\_Otto](https://boards.straightdope.com/u/Dag_Otto)\ **Post date:** [January 17, 2011, 5:38pm UTC](https://boards.straightdope.com/t/giant-rocks-falling-from-the-sky/567888/42 "2011-01-17T17:38:20Z")
The solution is simple: we set our clocks forward 12 hours, confusing the rock. The rock will adjust it’s timing 12 hours and hit somewhere along the China-Mongolia border, and who cares about that? NYC saved! YAY! Actually, I suggest that we set the clocks back 12 hours. Same result, and I could use the extra sleep. ---
**Author:** ![meldiocre](https://avatars.discourse-cdn.com/v4/letter/m/5f9b8f/32.png) [@meldiocre](https://boards.straightdope.com/u/meldiocre)\ **Post date:** [January 17, 2011, 5:44pm UTC](https://boards.straightdope.com/t/giant-rocks-falling-from-the-sky/567888/43 "2011-01-17T17:44:45Z")
i maintain that if dust blotting out the sun is the problem when the meteor hits, you move the stuff that would cause the dust out of the meteor’s way. and furthermore: > [@](#): > > I will say, though that thinking like meldiocre’s is what leads to cutting edge technology THIS is what i’m taking away from this thread. ---
**Author:** ![running\_coach](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/running_coach/32/15836_2.png) [@running\_coach](https://boards.straightdope.com/u/running_coach)\ **Post date:** [January 17, 2011, 5:49pm UTC](https://boards.straightdope.com/t/giant-rocks-falling-from-the-sky/567888/44 "2011-01-17T17:49:00Z")
> [@meldiocre](#): > > i maintain that if dust blotting out the sun is the problem when the meteor hits, you move the stuff that would cause the dust out of the meteor’s way. and furthermore: > > THIS is what i’m taking away from this thread. The whole damned crust makes the dust. Where do you plan to put it? So the whole thread is pointing out the physics of why it won’t work and all you get out of it is a compliment from someone who is just as ignorant. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [January 17, 2011, 5:49pm UTC](https://boards.straightdope.com/t/giant-rocks-falling-from-the-sky/567888/45 "2011-01-17T17:49:44Z")
Quoth **Mijin** : > [@](#): > > It will initially be bounced into space, but then it will fall back down, centered on the location where Wile E Coyote is standing. Even simpler! So all we have to do is send Wile E. Coyote to the Moon, and then the asteroid won’t hit the Earth at all! ---
**Author:** ![meldiocre](https://avatars.discourse-cdn.com/v4/letter/m/5f9b8f/32.png) [@meldiocre](https://boards.straightdope.com/u/meldiocre)\ **Post date:** [January 17, 2011, 5:52pm UTC](https://boards.straightdope.com/t/giant-rocks-falling-from-the-sky/567888/46 "2011-01-17T17:52:10Z")
> [@runner pat](#): > > all you get out of it is a compliment yes, that’s what i said. i tend to focus on the positives. ---
**Author:** ![running\_coach](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/running_coach/32/15836_2.png) [@running\_coach](https://boards.straightdope.com/u/running_coach)\ **Post date:** [January 17, 2011, 5:58pm UTC](https://boards.straightdope.com/t/giant-rocks-falling-from-the-sky/567888/47 "2011-01-17T17:58:21Z")
> [@meldiocre](#): > > yes, that’s what i said. i tend to focus on the positives. So you learned nothing? ---
**Author:** ![DrFidelius](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/drfidelius/32/3447_2.png) [@DrFidelius](https://boards.straightdope.com/u/DrFidelius)\ **Post date:** [January 17, 2011, 5:59pm UTC](https://boards.straightdope.com/t/giant-rocks-falling-from-the-sky/567888/48 "2011-01-17T17:59:53Z")
> [@Chronos](#): > > Quoth **Mijin** :Even simpler! So all we have to do is send Wile E. Coyote to the Moon, and then the asteroid won’t hit the Earth at all! If we provide Wile E. Coyote with an Acme Anti-Asteroid Umbrella, he will be fine. Maybe he will be umbrella-bell-shaped for a short time, but otherwise fine. The umbrella will come through without a scratch. ---
**Author:** ![meldiocre](https://avatars.discourse-cdn.com/v4/letter/m/5f9b8f/32.png) [@meldiocre](https://boards.straightdope.com/u/meldiocre)\ **Post date:** [January 17, 2011, 6:02pm UTC](https://boards.straightdope.com/t/giant-rocks-falling-from-the-sky/567888/49 "2011-01-17T18:02:20Z")
> [@runner pat](#): > > So you learned nothing? i learned that when you’re a charter member, you probably don’t have to follow the single rule of membership that closely. ---
**Author:** ![DrFidelius](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/drfidelius/32/3447_2.png) [@DrFidelius](https://boards.straightdope.com/u/DrFidelius)\ **Post date:** [January 17, 2011, 6:09pm UTC](https://boards.straightdope.com/t/giant-rocks-falling-from-the-sky/567888/50 "2011-01-17T18:09:52Z")
Oh, and to the OP – There is no measurable difference between an impact at ground level and an impact in a hole a mile deep. The speeds and energy levels involved in an asteroid strike cannot be contained by just digging a hole for the asteroid to fall in to. There is nothing we can conceivably make that is “indestructable” enough to line the hole to prevent this damage. ---
**Author:** ![meldiocre](https://avatars.discourse-cdn.com/v4/letter/m/5f9b8f/32.png) [@meldiocre](https://boards.straightdope.com/u/meldiocre)\ **Post date:** [January 17, 2011, 6:19pm UTC](https://boards.straightdope.com/t/giant-rocks-falling-from-the-sky/567888/51 "2011-01-17T18:19:31Z")
i mean… forget the unobtainium thing. i was simply thinking that if you dont want the pie on the window sill to make a mess in your house cuz the kids are throwing a ball around, you move the pie. if theres no pie (i.e. dust) then it cant make a mess (i.e. blot out the sun). no? all ive pretty much heard from you intellectuals is “lol ur dum”, i haven’t really gotten a reason that it wouldnt work to _move the dust-causing materials_ since the dust is the problem in the end. if i want to hear “lol ur dum” i can post the question on the wow forums or 4chan or something. ---
**Author:** ![Exapno\_Mapcase](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/exapno_mapcase/32/1051_2.png) [@Exapno\_Mapcase](https://boards.straightdope.com/u/Exapno_Mapcase)\ **Post date:** [January 17, 2011, 6:21pm UTC](https://boards.straightdope.com/t/giant-rocks-falling-from-the-sky/567888/52 "2011-01-17T18:21:36Z")
You’re not throwing a ball at the window. You’re thowing a stick of dynamite through the window. The pie will be ruined no matter where it is in the house. ---
**Author:** ![running\_coach](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/running_coach/32/15836_2.png) [@running\_coach](https://boards.straightdope.com/u/running_coach)\ **Post date:** [January 17, 2011, 6:23pm UTC](https://boards.straightdope.com/t/giant-rocks-falling-from-the-sky/567888/53 "2011-01-17T18:23:20Z")
The dust is the vaporized meteor and crust. What do you plan to move? ---
**Author:** ![DrFidelius](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/drfidelius/32/3447_2.png) [@DrFidelius](https://boards.straightdope.com/u/DrFidelius)\ **Post date:** [January 17, 2011, 6:25pm UTC](https://boards.straightdope.com/t/giant-rocks-falling-from-the-sky/567888/54 "2011-01-17T18:25:41Z")
Any part of the Earth that is hit by an asteroid is going to turn to dust, a lot of dust, and digging down through the crust would just make it easier for the impact to break through to the mantle (which would be even worse – picture the oceans pouring into a heat source that is big enough to boil all of the surface water of the world). ---
**Author:** ![meldiocre](https://avatars.discourse-cdn.com/v4/letter/m/5f9b8f/32.png) [@meldiocre](https://boards.straightdope.com/u/meldiocre)\ **Post date:** [January 17, 2011, 6:30pm UTC](https://boards.straightdope.com/t/giant-rocks-falling-from-the-sky/567888/55 "2011-01-17T18:30:23Z")
i dont know, pat. i was just thinking that if the hole was deep enough, the dust would have farther to travel and maybe instead of creating an impenetrable ring of death around the earth, a lot of it would be caught up in a subterranean dust-grotto. also yeah the thing about the oceans sounds pretty bad. ---
**Author:** ![Jake](https://avatars.discourse-cdn.com/v4/letter/j/f475e1/32.png) [@Jake](https://boards.straightdope.com/u/Jake)\ **Post date:** [January 17, 2011, 6:48pm UTC](https://boards.straightdope.com/t/giant-rocks-falling-from-the-sky/567888/56 "2011-01-17T18:48:08Z")
Sending out nukes to move the asteroid won’t work. The EPA would be all over you for polluting outer space with radiation. ---
**Author:** ![clairobscur](https://avatars.discourse-cdn.com/v4/letter/c/839c29/32.png) [@clairobscur](https://boards.straightdope.com/u/clairobscur)\ **Post date:** [January 17, 2011, 7:02pm UTC](https://boards.straightdope.com/t/giant-rocks-falling-from-the-sky/567888/57 "2011-01-17T19:02:48Z")
> [@GoodOmens](#): > > Assuming that we had enough advanced warning of a significant meteor heading our way, and even if we could predict its exact site and angle of impact, there are really on 3 things that we could do: > > 1. Launch a bunch of nukes at it. It wouldn’t help but it would look awesome. If I’m not mistaken, launching nukes at the meteor isn’t considered an useful solution. What should apparently be done would be landing rockets on it and use the rocket’s thrust to slightly alter the course of the meteor (given enough warning time, a very small change in the initial trajectory would eventually alter it enough that it could “miss” the earth). Not sure this could work with an extinction-event sized meteor. I’ve no clue about the mass of such an object, let alone if it would be feasible for us to alter significantly the trajectory of a body that large. ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [January 17, 2011, 7:04pm UTC](https://boards.straightdope.com/t/giant-rocks-falling-from-the-sky/567888/58 "2011-01-17T19:04:54Z")
> [@meldiocre](#): > > i dont know, pat. i was just thinking that if the hole was deep enough, the dust would have farther to travel and maybe instead of creating an impenetrable ring of death around the earth, a lot of it would be caught up in a subterranean dust-grotto. The dust isn’t so much projected into the atmosphere by the force of the impact, but rather drawn up by the rising mass of superheated gases produced by it. The height that column will reach is determined by the heat of those gases and the density profile of the atmosphere. If we are talking about a large object, so much energy is involved that the debris cloud will rise into the stratosphere, no matter how deep the hole is. (In any case, since the stratosphere starts at about 10 km up, you would have to dig a heck of a hole to equal its depth in the first place.) ---
**Author:** ![LouisB](https://avatars.discourse-cdn.com/v4/letter/l/dfb087/32.png) [@LouisB](https://boards.straightdope.com/u/LouisB)\ **Post date:** [January 17, 2011, 7:25pm UTC](https://boards.straightdope.com/t/giant-rocks-falling-from-the-sky/567888/59 "2011-01-17T19:25:47Z")
You guys worry too much. I saw a movie when I was a teenager where an asteroid was going to smash the earth to hell and gone and every nation on earth worked together to lay pipelines all the way to the south pole and then light off the natural gas in those pipes and the thrust changed the earth’s orbit enough to move it out of harms way and the asteroid went hurtling by, muttering curses and the earth was saved. Laying the pipe lines took like three days and everyone spoke English, even though it was a Japanese movie. Well, actually, it was a documentary and not a movie. I remember it and if it worked once, it would work again. Don’t sweat it. ---
**Author:** ![meldiocre](https://avatars.discourse-cdn.com/v4/letter/m/5f9b8f/32.png) [@meldiocre](https://boards.straightdope.com/u/meldiocre)\ **Post date:** [January 17, 2011, 7:32pm UTC](https://boards.straightdope.com/t/giant-rocks-falling-from-the-sky/567888/60 "2011-01-17T19:32:32Z")
> [@Colibri](#): > > The dust isn’t so much projected into the atmosphere by the force of the impact, but rather drawn up by the rising mass of superheated gases produced by it. The height that column will reach is determined by the heat of those gases and the density profile of the atmosphere. If we are talking about a large object, so much energy is involved that the debris cloud will rise into the stratosphere, no matter how deep the hole is. (In any case, since the stratosphere starts at about 10 km up, you would have to dig a heck of a hole to equal its depth in the first place.) okay, THAT makes sense. thank you for that. i promise my next question will be better. 😃 [Previous page](https://boards.straightdope.com/t/giant-rocks-falling-from-the-sky/567888.md?page=2) [Next page](https://boards.straightdope.com/t/giant-rocks-falling-from-the-sky/567888.md?page=4)