Planet sailing through the cosmos very fast?

[Baby Astronaut]

Can a planet be hurled by a star that's gone nova, or by any other means? If so, would it careen through space at high velocity, and keep its pace, seeing as objects in motion don't slow down unless acted upon by a force?

 

Or would intergalactic gravity slow and trap it? However, if so, what if that event occurred in a nearby star in our galaxy -- would the planet be able to cruise through our planetary system at near its original high velocity?

 

I'm just testing the feasibility of an external planet colliding into Jupiter or a smaller planet (like Mars/Earth/Venus).

[NowThatWeKnow]

I asked a similar question about supernovae a couple of months ago but it concerned smaller debris, not planets. It seems that I was told that the inertial frames would slow down over distance. Because of space dust and stuff at rest with the solar system and local gravitational fields also at rest.

 

Where you been Baby Astronaut?

[Martin]

At the risk of adding confusion, I just want to contribute some links about one kind of high speed post-supernova remnant

 

http://www.astronomy.com/asy/default.aspx?c=a&id=3471

(a neutron star leaving our galaxy at 1100 kilometers a second.)

 

http://arxiv.org/abs/astro-ph/0608205

(neutron star going 1600 km/s)

 

http://www.space.com/scienceastronomy/050906_fast_star.html

(more about B1508)

 

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I don't remember how the earlier discussion went but I agree that the diffuse blow-off from a supernova would typically be slowed down by gravity and the surrounding interstellar medium.

 

Gas, dust, lightweight stuff like that. I guess it would form an expanding sphere. That would interact with the surrounding stuff, and glow hot. I've seen pictures of that---looking like hot rings of glowing gas. You only see a circular section of the expanding sphere.

 

I don't know about anything planet-size. Except for the neutron star core remnant. Compact debris wouldn't be slowed down in the same way as gas etc.

 

A single massive star can collapse in a lopsided asymmetric way that gives the core remnant a kick.

 

Also some supernovas involve a binary system, and one partner might be a neutron star and it might get slung out when the star it was orbiting blows up.

 

There should be some discussion of at least the first case, in these links.

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1000 km/s is pretty fast. The earth in its orbit around the sun only goes 30 km/s and the solar system in its orbit around the center of our galaxy only goes about 250 km/s as I recall. And we don't notice that because all the stars in our immediate neighborhood are like a flock of birds all flying in much the same direction, all orbiting the center of the galaxy in about the same direction.

 

So we typically dont see relative motion of compact objects that is as fast as 1000 clicks.

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It should however be mentioned that space is fantastically big, so the liklihood of any compact object buzzing the solar system, or bashing one of our planets, is ridiculously small. It is only a theoretical possibility that one day a neutron star (of approximately the same mass as the sun) crashes into the sun at 1000 km/s and good-bye sun. It just isn't realistic to contemplate such things. :(

Edited April 24, 2009 by Martin

[norefillsx]

I think that when a star supernovas, the solar system it has is vaporized instantly, unless it has planets very very very far away from it, which is probably true in some cases, its the universe ya know, anything can happen..So i guess yes, that a planet could careen through space until gravity takes ahold of it, or it runs into something

[GDG]

Can a planet be hurled by a star that's gone nova, or by any other means? If so, would it careen through space at high velocity, and keep its pace, seeing as objects in motion don't slow down unless acted upon by a force?

 

Or would intergalactic gravity slow and trap it? However, if so, what if that event occurred in a nearby star in our galaxy -- would the planet be able to cruise through our planetary system at near its original high velocity?

 

I'm just testing the feasibility of an external planet colliding into Jupiter or a smaller planet (like Mars/Earth/Venus).

 

Planets can be ejected from a solar system by gravitational interaction with other planets or a passing star.

 

The galaxy does have gravity. Whether your passing planet kept its original velocity or not would depend to some extent on whether is was headed in or out. If headed toward the galactic center, it might even be accelerating.

 

Actual planetary collision is probably not as likely as a gravitational pas de deux, resulting in the planet in a new orbit (or possibly ejected from the system). However, there are plenty of craters in our system that attest to the fact that astronomical collisons do occur.

[Airbrush]

Suppose a planet-sized object gets thrown at high speed away from a supernova. It would be slowed by gas and dust friction somewhat. It's path would be bent by nearby stars, but it would be going too fast to be captured in orbit around any star, unless it slowed down very much.

[Baby Astronaut]

Suppose a planet-sized object gets thrown at high speed away from a supernova. It would be slowed by gas and dust friction somewhat. It's path would be bent by nearby stars, but it would be going too fast to be captured in orbit around any star, unless it slowed down very much.

Like if a black hole captured it.

 

Where you been Baby Astronaut?

Mostly lurking here, yet I've been posting around in other sections. Thanks for asking.