Where is planet earth heading?

[Jet2]

Earth is spinning everyday.

I assume this spinning action would make the planet move even though it may be sooooo slow that it may only move a cm in many billions year.

But, does anybody know...

 

Are we getting closer to the Sun?

Or getting away from it?

[sanctus]

Is there any logical reason why it should go away?

 

Eventually it will fall just into the sun, but probably the sun becomes a nova first...

But this has little to do with the spinning, more with the orbit around the sun. I say little because I can imagine well that since earth is not a perfect sphere there may be some little influence of its kinetic moment.

[Overdog]

Well, this link isn't exactly what you are asking, but I think it gives a pretty good answer...at least up to the point where the question becomes moot.:)

 

Archive of Astronomy Questions and Answers

[Moontanman]

Earth is spinning everyday.

I assume this spinning action would make the planet move even though it may be sooooo slow that it may only move a cm in many billions year.

But, does anybody know...

 

Are we getting closer to the Sun?

Or getting away from it?

 

Always closer, the Earth is very slowly spiraling down toward the sun and the sun is expanding it's surface toward the earth. The motion of the earth toward the sun is not significant but the other is.

[modest]

There are areas in the solar system where orbits are more chaotic and less likely to remain stable for billions of years. Between Venus and the asteroid belt there is greater long term stability over very long time periods. So, earth's orbit is very stable.

 

The long-term evolution of orbits in the solar system - A mapping approach

 

Earth's orbit - Wikipedia, the free encyclopedia

 

It is, however, true that as the sun looses mass (which it does very, very slowly), Earth's orbit will increase or our distance from the sun will increase. Also, as Earth transfers its kinetic energy to the interplanetary medium, its orbit will become smaller. These are very small factors. Earth has maintained stability for over 4 billion years and there is no reason to assume it won't be stable for another 4 billion - outlasting our star :).

 

~modest

[Reaper]

All orbits decay, but as everyone else here has pointed out it takes a very, very long time. Earth will certainly be orbiting the sun for much longer than the age of the universe, unless Andromeda knocks it away (or into the sun) 3 billion years down the road....

[Overdog]

"Earth is like a bus loaded with people, barreling down a mostly empty highway, with no one at the wheel."

 

Read that somewhere...

[REASON]

Earth has maintained stability for over 4 billion years and there is no reason to assume it won't be stable for another 4 billion - outlasting our star.

 

:)

 

I'm confused about this last statement I bolded. How can the Earth's stability, or orbit around the Sun outlast the Sun?

 

Current theory suggests that the Earth will be engulfed by the Sun during it's expansion. At the least I would expect the Earth's orbit to be significantly altered during the expansion period, the nova Planetary Nebula period, and the period of retraction to a White Dwarf state.

[Reaper]

Current theory suggests that the Earth will be engulfed by the Sun during it's expansion. At the least I would expect the Earth's orbit to be significantly altered during the expansion period, the nova period, and the period of retraction to a White Dwarf state.

 

 

Not quite. It is also predicted that the Earth likely will be pushed out further during the time the sun expands into a Red Giant due to increasing solar winds. In any event, the Earth will still orbit the Sun just fine. As to whether or not the biosphere on Earth will still be around is another issue all together.

[modest]

Earth has maintained stability for over 4 billion years and there is no reason to assume it won't be stable for another 4 billion - outlasting our star.

 

:)

 

I'm confused about this last statement I bolded. How can the Earth's stability, or orbit around the Sun outlast the Sun?

 

You're right. I meant 'outlast the main sequence lifetime' I don't think it's so easy to say one way or the other if earth will survive the transition past this to a red giant then white dwarf. I was trying to say that the sun would, in all likelihood, loose stability first and I should not have taken that idea further and stated so definitely that earth would survive.

 

Current theory suggests that the Earth will be engulfed by the Sun during it's expansion. At the least I would expect the Earth's orbit to be significantly altered during the expansion period, the nova period, and the period of retraction to a White Dwarf state.

 

Small matter, but there is no 'nova' phase. When the red giant throws off its outer layers forming a nebula it is still in the red giant phase - right up until the white dwarf phase. A nova is a different stellar process.

 

As the sun expands it will loose mass (ejecting it). Kepler's laws then necessitate the earth get farther away from the sun. This is not (as Reaper describes above) the result of the ejecta pushing on the earth, but just conservation of angular momentum. If the sun looses something like 20 percent of its mass then the earth will be far enough away to survive the transition to a white dwarf. If the earth does survive to this point, I have no idea what would happen next.

 

~modest

 

EDITED - I edited a few sentences above - more than just typos.

[REASON]

Not quite. It is also predicted that the Earth likely will be pushed out further during the time the sun expands into a Red Giant due to increasing solar winds. In any event, the Earth will still orbit the Sun just fine. As to whether or not the biosphere on Earth will still be around is another issue all together.

 

I know. That's one theory. A more recent model suggests otherwise according to the Wiki article on the Earth's future.

 

Earth - Wikipedia, the free encyclopedia

 

The Sun, as part of its evolution, will expand to a red giant in about 5 Gyr. Models predict that the Sun will expand out to about 250 times its present size, roughly 1 AU (150,000,000 km).[130][135] Earth's fate is less clear. As a red giant, the Sun will lose roughly 30% of its mass, so, without tidal effects, the Earth will be in an orbit 1.7 AU (250,000,000 km) from the Sun when the star reaches it maximum radius. Therefore, the planet is expected to escape envelopment by the expanded Sun's sparse outer atmosphere, though most, if not all, existing life will be destroyed because of the Sun's increased luminosity.[130] However, a more recent simulation indicates that Earth's orbit will decay due to tidal effects and drag, causing it to enter the red giant Sun's atmosphere and be destroyed.[135]

 

(Emphasis is mine)

[REASON]

Small matter, but there is no 'nova' phase. When the red giant throws off its outer layers forming a nebula it is still in the red giant phase - right up until the white dwarf phase. A nova is a different stellar process.

 

Your right. It's funny, I was editing my post to say "Planetary Nebula" instead of "Nova" while you were posting the reply above.

 

I stand erected.

[Reaper]

Ah, I see. Thanks. Through wikipedia, I found one such source for this: Hope dims that Earth will survive Sun's death - space - 22 February 2008 - New Scientist Space

 

This process has led some to speculate that the Earth might escape destruction – but survival now seems impossible, says Peter Schröder of the University of Guanajuato in Mexico and Robert Smith of the University of Sussex in the UK.

 

They created the most detailed model to date of the Sun’s transition to a red giant, based on observations of six nearby red giant stars. Sure enough, they found that Earth’s orbit will widen at first. But Earth will also induce a “tidal bulge” on the Sun’s surface, with its own gravitational pull. The bulge will lag just behind the Earth in its orbit, slowing it down enough to drag it to a fiery demise.

 

So yes, you are correct that the sun will probably crash right into the sun far sooner than I have stated. It will still be around for a few more billions of years though, so we can take comfort in that

[REASON]

So yes, you are correct that the sun will probably crash right into the sun far sooner than I have stated. It will still be around for a few more billions of years though, so we can take comfort in that

 

No question about that. Relative to our lifetimes, I have a difficult time imagining a million years, much less a few billion. :)

[raymond723]

I think the Mars could be the second earth