General Question moving celestial bodies with a motor?

[spec10]

Turning a celestial body into a "huge spaceship" sounds like fun, so I was wondering if it is possible to point a (strong enough) motor to the sky and move earth for example, or are celestial bodies on some "internal-rails" within orbiter?

 

[Artlav]

No, you can't move planets in Orbiter, not with engines.

 

[T.Neo]

In Orbiter, moving celestial bodies is not possible. Their path cannot be changed with rocket motors etc.

In real life, you will not be able to move a celestial body over a certain size due to gravitational, atmospheric or somesuch other factors. That and building a motor big enough would almost certainly be impossible.

But moving smaller objects (I.e. asteroids) should be possible given enough logistics and patience.

 

[spec10]

The problems in reality are clear to me, but in Orbiter those real-life problems making the venture a no go wouldn't be a factor I guess, since I can give a tiny motor a gigantic thrust value if i want to. So the only show stopper is the built-in thing that prevents this custom celestial body movement. well, time to build a huge deathstar-vessel.

Thanks for the clarification

 

[Sky Captain]

I discovered this the hard way when I tried to deorbit Moon with very powerful ship and Moon just continued to orbit happily.

 

[Dig Gil]

LOL, Sky Captain.
I've also thought about this before. I've already knew that would be impossible in the simulator: computer software works that way.
In real life I wouldn't think it to be impossible... unless you are limited to Earth resources to build the Mother of All Engines.

 

[Artlav]

Then again, no one told that you can't do it in Orbiter.

 

[T.Neo]

Well, you can change planetary attributes if you alter their .CFG files.

 

[Sky Captain]

How to move the Moon (with more or less off the shelf technology)

1. build the biggest hydrogen bomb possible

2. dig a deep shaft on the Moon (to compress the blast and direct it up like a rocket nozzle)

3. place the bomb in the bottom of the shaft and detonate.

4. repeat the process few million times.

 

[Lucy]

I'd imagine you're much more likely to blow vast chunks off the moon doing that. The resultant forces and change in mass may very well move the moon, but still, that's hardly the point.

People don't tend to appreciate the moon so much when a Europe-sized chunk of it is hurtling towards them at pace, with nuclear fallout clinging to it.

 

[eveningsky339]

I discovered this the hard way when I tried to deorbit Moon with very powerful ship and Moon just continued to orbit happily.

Too much free time?

 

[n72.75]

In real life you would break through the earths crust and make a big mess.

 

[JamesG]

Yep. For all their massive scale, planets are really as delicate as a falling droplet of water. The Earth is really a ball of molten rock and metal with a paper thin skin of solid rock and gas. Smaller bodies like the Moon and Mars aren't as liquid, but at their scale, they would behave as such if pushed or collided with. Smaller asteroids and the dwarf planets also would be tricky to move. Most are not a homogenous lump of rock, but a collection of aggrigate rocks and dust held together by their collective gravity. Applying a force against that is as likely to break it up as move it.

The only "practical" way to move a mass of any significant scale is with gravity. Using another, slightly smaller body's gravity to influence the object you want to move. The ultimate "planet mover" would be a singularity (black hole) that you could some how turn on and off.

 

[Dig Gil]

Never thought about that...

About the black hole... Humm.... let's call 3 squirrels to help us:

Alternatively (to fantasy) there's sci-fi... so bad it's not possible in Orbiter or real life.

This concept was in my list of things that could save the Earth from the end of the world.

 

[Sky Captain]

Ah, moving a planet is easy, you just need a World Engine

 

[Dig Gil]

Cool, a Sci-fi flick with unsynchronized sound!

 

[Andy44]

Moving a large body is theoretically possible, of course, but there is only thing required by Isaac Newton: You need to eject mass away from the planet.

Simply sticking a rocket nose-down in your back yard won't work, for two reasons:

1. The rocket's exhaust will loose all it's momentum after traveling up through the atmosphere for a few hundred feet.

2. Even without an atmosphere, a chemical rocket's exhaust cannot reach Earth escape velocity, and thus all those gas molecules roaring out the rocket's nozzle will fly up into the sky and then fall back to the surface. The exhaust mass must escape the body's sphere of influence in order to create thrust.

On the moon, of course, point number 2 is the only one you need to worry about.

Now, if it makes you feel any better, we have moved planets, including the Earth and the Moon, already! Every time we launch a spacecraft and inject it into an escape trajectory, we have expelled part of the Earth's mass in one direction, creating an equal and opposite reaction in the other. (Which, of course, is so small that you can't even measure it, so it's really just a thought experiment.)

We've also launched and landed and crashed objects on the moon as well, and we've performed slingshots on all the other planets save Pluto, which will get a flyby visit in a few years.