Flight Question Knowing when to launch from Earth for Earth-Moon or Earth-Mars travel

[Alexrey]

Hi guys,

I'm trying to figure out, in general, the best time to launch from Earth if I want to minimize the delta-v required to align planes with the Moon or Mars before I start the Trans-Lunar or Trans-Mars injection. So far I've got it horribly wrong, usually 50 degrees off, effectively destroying my mission before I've even begun.

 

[Ripley]

50 degrees are way too many!
Try to minimize the deviation between orbital planes during ascent itself.

You could give a shot at LaunchMFD:
[ame="http://www.orbithangar.com/searchid.php?ID=2802"]Launch MFD - v. 1.6.2 for Orbiter 2010[/ame]

 

[Alexrey]

Is there a way to do it manually without the use of MFDs?

 

[garyw]

Sure.

For the moon launch whenever you want and go due East. You can then do an off-plane intercept with the moon.

For Mars, date is more important thanks to the dV required to get to Mars. You should also launch due East and fly an off-plane intercept.

 

[Enjo]

Hey, this sounds easy! Looks like it's not a problem that I've actually forgotten how to USE Orbiter in the years after all.

 

[blixel]

Hi guys,

I'm trying to figure out, in general, the best time to launch from Earth if I want to minimize the delta-v required to align planes with the Moon or Mars before I start the Trans-Lunar or Trans-Mars injection.

With regards to the moon, see if this video helps your understanding of when to launch: