Do galaxies have a "bow-shock"

[hungrrrry1]

I'm not a space scientist, just an enthusiast and thought if a moon or planet is used for a gravitational sling-shot to accelerate spacecraft...would our solar system's bow shock have a similar effect?...what about a galaxy?

 

[heyscottie]

You could use the solar system (which really just means using the sun) to increase your speed through the galaxy. Note that your speed relative to our solar system would not change. Same goes for the galaxy -- you could change your velocity relative to some other target outside of our galaxy, but not relative to the galaxy.

 

[michaelmozina]

That's an interesting question actually. The answer is likely to be "yes", but then you'll have to identify the material that is "running into" the galaxy, and which direction(s) it's coming from.<br /><br />Recent Voyager data suggests that the sun has a teardrop shaped heliosphere around it, suggesting that plasma is flowing into our system from the southern hemisphere, or a sun is moving toward the southern hemisphere. It's possible that the whole galaxy has a electromagnetic sphere around it as well, and that material flows into it from a specific direction too. I think the answer is probably yes. <div class="Discussion_UserSignature"> It seems to be a natural consequence of our points of view to assume that the whole of space is filled with electrons and flying electric ions of all kinds. - Kristian Birkeland </div>

 

[yevaud]

On the one hand, an image of merging Galactic Clusters. Note the bow shock on the right.<br /><br />Image<br /><br />On the other, no, I rather doubt the mechanism would be useful for gravitational accelerating a craft. <div class="Discussion_UserSignature"> <p><em>Differential Diagnosis:  </em>"<strong><em>I am both amused and annoyed that you think I should be less stubborn than you are</em></strong>."<br /> </p> </div>

 

[michaelmozina]

Keep in mind that bow shock and the sling shot effect are different issues by the way. <div class="Discussion_UserSignature"> It seems to be a natural consequence of our points of view to assume that the whole of space is filled with electrons and flying electric ions of all kinds. - Kristian Birkeland </div>

 

[robnissen]

<font color="yellow">Note the bow shock on the right.</font><br /><br />Yes, but. I am quite sure there is a bow shock when one galaxy hits another as in the link you posted, but the question is, is there enough inter-galactic "stuff" for a galaxy to run into when it is not hitting another galaxy. My guess is that there is not enough intergalactic stuff to form a bow shock.

 

[yevaud]

I really don't think there's some cut-off point at which there is no bow-shock present. As to whether or not it has any real force behind it, or for that matter luminesces enough for us to directly image it, is not an issue.<br /><br />After all, even a few wisps of trace gas in the Intergalactic void still would be affected. <div class="Discussion_UserSignature"> <p><em>Differential Diagnosis:  </em>"<strong><em>I am both amused and annoyed that you think I should be less stubborn than you are</em></strong>."<br /> </p> </div>

 

[michaelmozina]

I agree with you about even trace amounts of gases being affected by the way.<br /><br />FYI, there is a significant difference in how one percieves this issue depending on whether or not one puts faith in plasma cosmology theory. In EU/Plasma cosmology theory, there is always current running through all the threads of spacetime, and galaxies are "strung together" in energy flows of cosmic scale proportions. In that way of viewing the universe, all galaxies are bound to experience some sort of "bow shock" at the point where the current (electron and positive ion) flows into the galaxy and out the other side. In other words, in EU theory it would be likely that there would be electron flows and ion flows to consider as it relates to large scale bow shock events. One's choice of favorite large scale astronomy theories tends to play a large role in one's assumptions and perceptions. <div class="Discussion_UserSignature"> It seems to be a natural consequence of our points of view to assume that the whole of space is filled with electrons and flying electric ions of all kinds. - Kristian Birkeland </div>

 

[h2ouniverse]

In reply to: "gravitational sling-shot to accelerate spacecraft...would our solar system's bow shock have a similar effect?..."<br /><br />Hungry,<br />I do not think thebow shock would be of great use for a gravitational sling shot.<br />Its overall mass is, as an order of magnitude, about 1/1000 of Pluto's... Spread over hundreds of AU. So its gravitational field is negligible. Better use the dwarf planets or big objects of the Extended Kuiper Belt and of the Oort Cloud. For a sling shot effect, you need to arrive somewhat parallel to the velocity vector of the object that you use for the slingshot.<br /><br />It is "rich" in Hydrogen so you can think of collecting it on the way but be patient, its density is just about 1e-21 kg/m3 (accounting for H plus He).<br /><br />Best regards.

 

[hungrrrry1]

Thanks...I figured a bit as much...so then...<br /><br />...using KBO's for gravitational slingshot, given that there are plenty out there...wouldn't we have an unlimited potential for dramatic increases in speed for craft exploring the outer solar system or maybe a serious effort to eject a vehicle from the solar system completely...In essence...if we have a craft now that has achieved 85,000 mph in space...would this be viable to reach speeds of 200,000 mph, 500,000 mph...a million mph??? <br />Certainly we can create a craft to specialize in located the best and nearest KBO's for this purpose and just send instruments along with it....I would assume it would need to be a rugged craft <img src="/images/icons/wink.gif" /><br /><br />

 

[MeteorWayne]

Welcome.<br /><br />Really, the objects in the Kuiper belt are so far apart, and so small (masswise) that there's just not much gain in speed there to harvest. Unless you want to skim within a kilometer of an object where the +/- on elevation is 5 km. That could end very badly, especially if you plan to try it 20 or 30 times to gain the kind of increases you are talking about. <br /><br />Just my view.<br />MW <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[yevaud]

I suppose I will have to tend to agree with you. Reason: the periodic end result of extreme Bow-Shock: explosive reconnection. <div class="Discussion_UserSignature"> <p><em>Differential Diagnosis:  </em>"<strong><em>I am both amused and annoyed that you think I should be less stubborn than you are</em></strong>."<br /> </p> </div>