View Full Version : Do humans have the ability to send the earth spiralling in to the sun?
08-17-2001, 11:19 AM
Do we have the technology to do it? I'm thinking sending up one nuclear missile after another in to low earth orbit, position it in the path of the earth's revolution around the sun, and knock it "back" slightly, slowing it down. Do this over, and over, and over, and over until the earth is gradually pulled in to the sun...
08-17-2001, 11:23 AM
I don't know about then nuke strategy, but some have postulated that they could change the course of asteroids (maybe also with nukes) so that they do a near-miss with the Earth, but effect the Earth's orbit. The goal here is to move the Earth AWAY from the sun as it begins to expand a few million years, but I suppose the same concept could be used to kill the Earth to, if that's how you're bent.
08-17-2001, 11:41 AM
I would suppose this is theoretically possible but practically impossible.
The earth has a HUGE amount of inertia that would need to be overcome. Blowing up nukes nearby would barely nudge the earth. Frankly I think you'd end up irradiating earth to the point of killing all life LONG before you got it to spiral into the sun.
The same thing goes for asteroids. You'd need an awful lot of them to noticeably affect the orbit of the earth. The moon is pretty damn big compared to an asteroid and the best it does is introduce a slight wobble in earth's orbit. Maybe if the moon stopped somewhere off to the side of earth's orbital path you might slowly drag the earth away from it's trajectory but I'm not even sure about that.
FWIW the earth is actually slowly spiraling into the sun right now. Fortunately the energy loss the earth experiences is so small that our sun will burn out LONG (a very very long time) before we crash into it.
08-17-2001, 11:58 AM
08-17-2001, 12:03 PM
Originally posted by Whack-a-Mole
The same thing goes for asteroids. You'd need an awful lot of them to noticeably affect the orbit of the earth.
Actually, I think the concept was that the asteroid would be in an orbit that near-miss the Earth many times. Of course, the sun is expanding pretty slowly, so it doesn't have to have a quick effect like one would presumably desire when trying to destroy the Earth.
08-17-2001, 12:13 PM
Let's see, just a rough one here, but the earth weighs about 6 x 10^21 tons, or 1.2 x 10^25 pounds, and it is travelling a circle with radius of 9.3 x 10^7 miles in a period of one year, or about 5.84 x 10^8 miles per year, or about 6.6 x 10^4 miles per hour. So the kinetic energy in English units is about .5mv^2 or (.5)(1.2 x 10^25)(6.6 x 10^4)pounds-miles^2/second^2. That's 4 x 10^29 pounds-miles^2/second^2, which translates into metric units roughtly as 1 shitload of energy.
08-17-2001, 12:58 PM
Niven wrote a novel a ways back where a technologically advanced civilization built an engine directly into Neptune using the planet's atmosphere as fuel. They then flew Neptune past the Earth, using its gravitational well to slingshot the Earth into orbit around Jupiter. Intriguing idea, but I think it'd take forever and a day.
08-17-2001, 01:44 PM
Man, that's the second time in a week that obscure Niven novel was mentioned. It was "A World Out of Time." It does bring up a good point, in that using the gravitational pull of another stellar body to move the Earth would be easier than slowing it down with a couple of well-placed nukes. Intertia is the problem; blow up a couple of H-Bombs to slow down the Earth, and everything that isn't fastened down will want to continue on in its path. Tug it along with another planet, and it just might work (though I seem to remember in the novel that there still was flooding and damage).
08-17-2001, 01:56 PM
Originally posted by Guy Propski
Intertia is the problem; blow up a couple of H-Bombs to slow down the Earth, and everything that isn't fastened down will want to continue on in its path.
"a couple of H-Bombs" wouldn't nearly be enough to come close to affecting the Earth's orbit (except to an immeasurable degree). As The Bad Astronomer points out in his review of Armegedden (http://www.badastronomy.com/bad/movies/armageddon.html), the amount of energy required to shove aside an asteroid is staggering; trying to move the Earth would be several orders of magnitude more difficult.
08-17-2001, 02:07 PM
We will be sure to find out once I get a few more responses to my Uranium thread.
08-17-2001, 02:38 PM
Another factor is that you would have to move humanity to another planet since as earth got closer to the sun the people doing the moving would die.
Nukes ar just not powerful enough but diverting an astroid into an earth-sun orbit might work but would be very difficult to maintain.
08-17-2001, 03:23 PM
Originally posted by Royal Sampler
Do we have the technology to do it?
Not yet, but these guys think we might someday...(in reverse application though)...
08-17-2001, 03:38 PM
Originally posted by jseigle
Let's see, just a rough one here, but the earth weighs about 6 x 10^21 tons, or 1.2 x 10^25 pounds...
Wow, that's way off... the earth only weighs about 5 pounds (http://boards.straightdope.com/sdmb/showthread.php?threadid=13796). See, if you get a scale and turn it upside down on the floor...
vBulletin® v3.7.3, Copyright ©2000-2013, Jelsoft Enterprises Ltd.