Had an, oh, that's how moment - Slingshot manuever

[thecow99]

Had an, "oh, that's how" moment - Slingshot manuever

So I've pondered on this off and on, could never see how it was possible, suddenly it just hit me.. tell me if I'm correct.

In order to gain speed the object is using the orbital (or simply directional) trajectory of another. It allows itself to be pulled/tugged/towed towards, ideally on the same trajectory as the object, siphoning off it's momentum into itself for a boost. I'm assuming the ejection trajectory must be quite steeper than the insertion in order maintain this momentum, taking advantage of the exponential drop off of gravitational pull over distance.

Makes sense to me, but did I get it right?

Thanks!

I can also see how coming in the opposite direction could also work as well, by not doing the math though I'm not sure which would produce a better result.

Sorry, also just realized this probably belongs in the Classical Physics thread. Don't know how to move/delete this original post.

 

[Drakkith]

Have you read this article?
http://en.wikipedia.org/wiki/Slingshot_manoeuvre

 

[mfb]

You cannot understand gravitational slingshots as two-body problem. Relative to the planet/moon where the slingshot happens, the initial and final speed are always the same*. The velocity relative to a third object (sun/planet) can increase in this process.

*without propulsion. With propulsion this would use the Oberth effect.

 

[thecow99]

Thank you both. Why, oh why, do I think about problems involving the word 'relative'? Tweaks my brain a bit but, at least, it forces me to flex it.

I'm going to have to do the math now as my explanation seemed perfectly reasonable. Give me a bit, possibly a couple days, I'm no student and this might take me a bit to wrap my head around.

Cheers!

 

[pmacias]

No problem, I am a scientist and I am happy to help! You are correct in your understanding of the slingshot maneuver. It is also known as the gravity assist maneuver and it is commonly used by spacecraft to gain speed and change direction in their orbits.

As you mentioned, the spacecraft takes advantage of the gravitational pull of another object, such as a planet or moon, to gain momentum. This is achieved by carefully planning the trajectory of the spacecraft so that it approaches the object at a specific angle and speed. As the spacecraft passes by the object, it is pulled towards it and its speed increases, while the object's speed decreases slightly.

The key to the success of the slingshot maneuver is the careful calculation of the angle and speed of approach. If done correctly, the spacecraft can gain a significant amount of speed without using any additional fuel. This makes it a cost-effective way to navigate through the solar system.

To answer your question about the direction of approach, both directions can work depending on the specific mission objectives. Coming in the opposite direction can also provide a boost in speed, but it may require more precise calculations and adjustments.

I hope this helps to clarify the concept of the slingshot maneuver. It is a fascinating application of classical physics and has been used in numerous space missions. Thank you for bringing up this interesting topic!