A wild theory.

[pioneer0333]

I don't think it is possible. But I wonder if we can use a black hole as a gravitational slingshot. And if so, would it give a bigger push than that of a star or a planet?<br /><br />Please respond. <div class="Discussion_UserSignature"> </div>

 

[vogon13]

Works just the same as long as the flight path doesn't penetrate the event horizon.<br /><br />However, the craft (or whatever is executing the manuveur) will need to withstand the tidal effects which can be largish above the event horizon.<br /><br /> <div class="Discussion_UserSignature"> <p><font color="#ff0000"><strong>TPTB went to Dallas and all I got was Plucked !!</strong></font></p><p><font color="#339966"><strong>So many people, so few recipes !!</strong></font></p><p><font color="#0000ff"><strong>Let's clean up this stinkhole !!</strong></font> </p> </div>

 

[trustno1fox2]

yeh, two risky As vogon stated. <br /><br />A planet is muuuuuuuuuchhh safer, because it is not trying to pull you in past its event horizon, to be squeezed into infinite density. lol. <br /><br />Though a planet could pull you in.........

 

[vogon13]

Radiation flux and accrection disc would be further navigation hazards.<br /><br />Shields up!<br /><br /> <div class="Discussion_UserSignature"> <p><font color="#ff0000"><strong>TPTB went to Dallas and all I got was Plucked !!</strong></font></p><p><font color="#339966"><strong>So many people, so few recipes !!</strong></font></p><p><font color="#0000ff"><strong>Let's clean up this stinkhole !!</strong></font> </p> </div>

 

[eric2006]

You do need a largish black hole to avoid tidal stretching. If the hole gobbled up all the matter around it then it shouldn't be belching up to many x-rays. <br /><br />You shouldn't feel the huge acceleration through the black hole's gravity. You'd be in free fall. Just fire your rockets as you are falling in. That should be the only thing you feel.<br /><br />As long as your timing is right - maybe get up to a good fraction of light speed. And if your timing was off ...... you would have forever to think about your mistake.

 

[spacester]

Actually, the answer is no. You cannot be in orbit around a body and use it as a 'slingshot'. You have to use a third body which is orbiting the same body you are.<br /><br />I hate the term 'slingshot' and this common misconception is why. Call it a "redirect' maneuver and you'll be closer to understanding the reality.<br /><br />If you are in Heliocentric (sun-centered) orbit and you make a close pass to the Sun, it's because you somehow established an orbit with a very low perigee. The so-called 'swing-by maneuver' is just a close pass, your orbit does not change a whit (unless you're going to use "corona braking", lol).<br /><br />A 'redirect maneuver' works like this: <br /><br />You're cruising along in orbit with the sun at one node of your elliptical path, just like all the planets. You happen to come close to a big ol' planet! OMG you get close enough to it that it starts bending your flight path! The closer you get, the more it bends your trajectory from the boring old heliocentric orbit you were on. You are getting re-directed!<br /><br />Whew! That was a close one! You ended up going whizzing by after all. But where are you going? Well, you do your vector arithmetic and plot your new heliocentric orbit. The trick to the math is this: conservation of momentum within the entire solar system dictates that your velocity magnitude *relative to the sun* pre-redirect is the same value as post-redirect. But you changed the direction.<br /><br />The redirect maneuver has the effect of "stealing" momentum from the target planet because it was pulling on the planet for a while, but it was never gravitationally 'bound' to the planet. This momentum exchange is reflected in the new orbital energy of your interplanetary cruiser, that energy is a result of the trick of keeping the velocity magnitude constant whille changing the direction. BTW, you pass on the inside of the planet to get redirected outwards, as in using Venus to get to Jupiter. You pass on the outside to get redirec <div class="Discussion_UserSignature"> </div>

 

[vogon13]

A craft out bound from the solar system could encounter a (conveniently located) black hole and use it for a trajectory modification. One could vary the approach angle and distance to utilize the black hole for a direction change.<br /><br />Also, the black hole is (presumably) in orbit about the center of our galaxy, as the sun is, so the criteria for a velocity change would exist.<br /><br /> <div class="Discussion_UserSignature"> <p><font color="#ff0000"><strong>TPTB went to Dallas and all I got was Plucked !!</strong></font></p><p><font color="#339966"><strong>So many people, so few recipes !!</strong></font></p><p><font color="#0000ff"><strong>Let's clean up this stinkhole !!</strong></font> </p> </div>

 

[spacester]

Ah, very good, my vogon friend. I didn't envision either of those scenarios. In the first one though, the black hole would be co-orbiting Sol.<br /><br />So uh, is there something we should know? Have you vogons been screwing around with black holes again? I thought there was a regulation against that. <div class="Discussion_UserSignature"> </div>

 

[newtonian]

Pioneer0333 - Holey (not Holy) travel!!!

 

[vogon13]

The black hole encounter was the only high point of my dreadful trip here to this woefully inadequate world.<br /><br /><img src="/images/icons/wink.gif" /><br /><br /> <div class="Discussion_UserSignature"> <p><font color="#ff0000"><strong>TPTB went to Dallas and all I got was Plucked !!</strong></font></p><p><font color="#339966"><strong>So many people, so few recipes !!</strong></font></p><p><font color="#0000ff"><strong>Let's clean up this stinkhole !!</strong></font> </p> </div>

 

[formulaterp]

<font color="yellow">conservation of momentum within the entire solar system dictates that your velocity magnitude *relative to the sun* pre-redirect is the same value as post-redirect.</font><br /><br />Is this correct? Or do you mean to say that the spacecraft's velocity relative to the planet is the same? Your velocity with respect to the Sun should increase (or decrease, depending).<br /><br />