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Bruno da Silva

Could anything change Earth's orbit?

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What does make the Earth be orbiting the Sun?

 

Gravity.

 

 

Would there be a way to change Earth's orbit?

 

Magic.

 

Or have I got those the wrong way round?

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So why doesn't the gravity make the Earth go straight to the Sun?

 

So you haven't got this far in school yet?

 

Basically, an orbit is an object falling as fast as the ground below it falls away. Imagine throwing a ball: it will go some distance then hit the ground. Now throw it harder: it will go further. Now imagine you could throw it so hard that it went to the horizon. But at that point the curvature of the Earth means that the ground has dropped away beneath it and so it keeps going.

 

Here: http://waowen.screaming.net/revision/force&motion/ncananim.htm

 

https://en.wikipedia.org/wiki/Newton%27s_cannonball

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So you haven't got this far in school yet?

 

Basically, an orbit is an object falling as fast as the ground below it falls away. Imagine throwing a ball: it will go some distance then hit the ground. Now throw it harder: it will go further. Now imagine you could throw it so hard that it went to the horizon. But at that point the curvature of the Earth means that the ground has dropped away beneath it and so it keeps going.

 

Here: http://waowen.screaming.net/revision/force&motion/ncananim.htm

 

https://en.wikipedia.org/wiki/Newton%27s_cannonball

 

What's the force that makes the Earth keep going straight ahead? If there's no force to make it go to the horizon, it would go straight to the Sun.

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What does make the Earth be orbiting the Sun? Would there be a way to change Earth's orbit?

Nothing really…but the Earth isn't quite as smart as Wile E. Coyote. Eventually it will figure it out though, gravity will take over, and the plummet to the Sun will quickly follow.

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Nothing really…but the Earth isn't quite as smart as Wile E. Coyote. Eventually it will figure it out though, gravity will take over, and the plummet to the Sun will quickly follow.

I'm sure you are wrong about that. In fact the Earth is slowly drifting away from the Sun as the Sun loses mass through energy generation.

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So you haven't got this far in school yet?

 

I know, and part of me feels horrible about a situation where ignorance of science is being used in such a plug-ugly way. I thought at first it was just because I favor expansion and exploration for the human race, but now I realize it's because Bruno da Silva has such a hideous approach to one of the most beautiful things I can imagine.

 

He asks questions about science the way someone would ask about the Mona Lisa if they just wanted to wipe their hands clean on it.

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Yeah. I was hoping the introduction to the very cool idea of orbits as continual falling might intrigue him and make him want to learn more....


I'm sure you are wrong about that. In fact the Earth is slowly drifting away from the Sun as the Sun loses mass through energy generation.

 

That "wooshing" noise you hear is the joke flying over your head...

Edited by Strange

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That "wooshing" noise you hear is the joke flying over your head...

 

ROFL, I thought for five minutes trying to come up with something like this, and was just overwhelmed by the options. Excellent Choice!

 

I think J.C.MacSwell should open a thread on Warner Bros Physics.

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ROFL, I thought for five minutes trying to come up with something like this, and was just overwhelmed by the options. Excellent Choice!

 

It did take me nearly 12 hours!

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ROFL, I thought for five minutes trying to come up with something like this, and was just overwhelmed by the options. Excellent Choice!

 

I think J.C.MacSwell should open a thread on Warner Bros Physics.

Should that be in the mainstream forum lol?

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Should that be in the mainstream forum lol?

 

As long as you aren't speculating on some kind of anti-gravity based on not knowing where your feet are, it should be OK in the mainstreams.

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What does make the Earth be orbiting the Sun?

I think it depends who you ask. If Einstein, then I believe what he would say is something like: the Earth travels in a straight line in curved space-time (the Sun's mass bends space-time). Others might say it's the centripetal force of gravity deflecting Earth's linear motion. And then perhaps others might say it's a centrifugal force countering the Sun's gravity.

 

Would there be a way to change Earth's orbit?

I think you will find that Earth's orbit changes all the time, such that no two orbits are exactly the same.

 

I even understand it's thought that larger fluctuations in Earth's orbit, resulting in climate extremes, which accounts for the development through evolution of our (what we like to think) large brain.

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Something that could change earths orbit without necessarily destroying would be something like a interstellar planet like object or a brown dwarf passing through the solar system and close enough to Earth for its gravitational pull to significantly alter the Earths trajectory. Based on the fact that the eight planets all have fairly stable circular orbits this probably has not happened before and is unlikely to happen in the foreseeable future.

 

When one object orbits another, it is falling, but missing the ground.


Eventually in 4 billion years or so the Sun will grow into a red giant and possibly big enough for the Earth to get swallowed by the sun.

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What does make the Earth be orbiting the Sun?

Acceleration of initial accretion disk

https://en.wikipedia.org/wiki/Accretion_disc.

 

Would there be a way to change Earth's orbit?

Yes.

f.e. direct collision with other cosmic object, resulting in rapid deceleration, or changing path (and vaporization of the all living organisms on the Earth).

It happens all the time but with small objects in f.e. kuiper belt.

f.e. indirect passing through massive cosmic object in close region of Solar System.

 

See thread about hypervelocity stars

http://www.scienceforums.net/topic/90600-hypervelocity-stars-new-mechanisms-of-creation/

This is pretty similar case, but with stars and black hole.

Cosmic object can be ejected from its normal path (better fate than being suck by black hole).

Edited by Sensei

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Something that could change earths orbit without necessarily destroying would be something like a interstellar planet like object or a brown dwarf passing through the solar system and close enough to Earth for its gravitational pull to significantly alter the Earths trajectory. Based on the fact that the eight planets all have fairly stable circular orbits this probably has not happened before and is unlikely to happen in the foreseeable future.

I think you will find that the idea is that the planets are not in their original positions - the large planets in particular. In fact I understand it's not known if the orbits could be described as stable. Not stable as there might be a configuration whereby a planet could drift off out of orbit. The reverse process of how some moons, I believe, are suggested to have been captured into an orbit.

 

And I think you will find that a circular orbit is a very rare occurrence - such that it's next to impossible. The Earth's orbit is not circular but elliptical whereby it's closer to the Sun when the northern hemisphere is in winter. Which means the Sun is not to even at the centre of Earth's non-circular orbit (if it were at the centre there would be two close occurrences and two farthest occurrences).

Edited by Delbert

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What does make the Earth be orbiting the Sun? Would there be a way to change Earth's orbit?

You could try running in the opposite direction ??

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Anything powerful enough to shift the orbit of any planet would fall into the category of "Things we don't need to worry about, because it would kill us all anyway."

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Anything powerful enough to shift the orbit of any planet would fall into the category of "Things we don't need to worry about, because it would kill us all anyway."

 

I will pedantically point out that this is a matter of degree, and not a categorical truth. The sun is continually losing mass, so our orbit (and the orbit of anything that orbits the sun) has got to be changing as a result. But it's a small effect. The sun loses 4 billion kg/s, meaning over 10^17 kg per year. But its mass is 2 x 10^30kg, so even in a billion years at that rate it's less than 1%.

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I will pedantically point out that this is a matter of degree, and not a categorical truth. The sun is continually losing mass, so our orbit (and the orbit of anything that orbits the sun) has got to be changing as a result. But it's a small effect. The sun loses 4 billion kg/s, meaning over 10^17 kg per year. But its mass is 2 x 10^30kg, so even in a billion years at that rate it's less than 1%.

Heh, fair point. :)

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