Aurora 4x

Off Topic => Off Topic => Topic started by: sublight on June 16, 2012, 11:16:09 AM

Title: Lagrange point course change
Post by: sublight on June 16, 2012, 11:16:09 AM
One of my hobbies is to plan hypothetical missions to other planets. Somehow researching launch vehicles, payload capacities, and scribbling out flight paths is kind of fun.

In my scribbles I think I figured out a Venus transfer orbit thats both faster and requires less velocity change than the classic Hoffman. Only trouble is, it starts off with a 16° course change from Earth's orbital path. If a constant velocity course change can be cheaply done then I'm on to something. If the redirect would have to be made entirely with a rocket burn then the plan may not be so grand.

So, does anyone know what sort of course changes are possible (relative to earth' solar orbit) from an earth escape trajectory using a lunar gravity maneuver or a Lagrange point? If none know, does anyone have any other message boards I might try asking?
Title: Re: Lagrange point course change
Post by: HaliRyan on June 16, 2012, 07:17:57 PM
Wait, so, your hobby is rocket science?

(I have no idea how to help you with this one, although I'm sure the resources must be out there)
Title: Re: Lagrange point course change
Post by: Erik L on June 16, 2012, 07:44:38 PM
Last time I checked, we do have a couple rocket scientists as members, along with a couple nuclear physicists.
Title: Re: Lagrange point course change
Post by: sublight on June 18, 2012, 06:22:16 PM
Wait, so, your hobby is rocket science?


Casual rocket science, but yes. I may be a newly minted computer programer by occupation, but at heart and education I'm an engineer. We like solving interesting problems, and if need be will invent new ones if existing problems are either lacking or boring.


Anyway, I think I've figured out why my brilliant I-can't-believe-no-one-has-thought-of-this solution isn't practical. Sure you can (in theory) make a 180° turn around a planet or Lagrange point, but when you're moving 30 km/s relative to the Sun, a likely 1km/s relative motion U-turn around the moon is small compared to both your sun-relative speed and the oberth effect potential at Earth itself.

I maybe sort of knew all this back when I first posted, but at the time watching my idea crash and burn I was stuck somewhere between denial and bargaining.