Getting there from here: tips for the ignorant on how to navigate between planets.

[Interplanet Janet]

On ‎3‎/‎23‎/‎2016 at 6:34 PM, SgtSomeone said:

There's a bunch of great web calculators our there, but I never managed to figure out how to use them (how do I measure my ejection angle? Burn angle? In reference to what now?). I don't have any relevant mods, so I've done Hohman transfers to every planet just using a window rule of thumb: start the Hohman transfer burn when the target planet (for those farther from Sol than Kerbin) is aligned with Kerbin's tangent line. IOW it's directly in the path that Kerbin would travel if suddenly gravity from Sol was no longer a thing. For inner planets, start the burn when Kerbin is aligned in the tangent of the target planet. It gets awkward for plane changes, but it'll get you where you need to go without that much of an efficiency hit.  

If you want to practice in a gentler environment, try going from the Mun to Minmus or vice-versa. Same principles apply (though there is a plane change)

In case I misunderstood and you were wondering about more efficiency, other factors to consider that I generally don't bother with:
-Oberth affect (rockets are more efficient when going faster, and thus a lower periapses); To get to Eloo it may actually be more efficient to first drop your periapsis below Eve's orbit. 
-Gravity assists: Useful around Jool and all the moons, but a real pain to figure out with planets. New Horizons did something like 5 Venus flybys, and I can't imagine trying to schedule those. 
-For shorter time (and more delta-v) try starting your Hohman early, and add more delta-v until you hit the planet. 

If you're looking for real inspiration, take a look at real NASA missions like Curiosity! 

https://en.wikipedia.org/wiki/Orbital_maneuver#Transfer_orbits

No, New Horizons just went straight to Jupiter en route to Pluto.

[SgtSomeone]

1 hour ago, Interplanet Janet said:

No, New Horizons just went straight to Jupiter en route to Pluto.

 

Ah, got my deep-space craft mixed up. I was thinking Galileo, who had only 1 Venus flyby, but had 2 earth flybys which greatly confused me when I first started learning this stuff ("how do you get more speed from the place you launched at! It's the same speed!?"). 

[RW-1]

On 3/23/2016 at 6:17 PM, Tourist said:

Before this year, who would of thought that Donald Trump could be president? I expect the 'Hoff' to setting off for Mars at anytime now. 

Can he take Trump (and quite a few other Celeb's) with him?

 

Kinda a reverse Zanti misfit's plot ....

Edited March 29, 2016 by RW-1

[Kyrt Malthorn]

I seem to be mediocre when it comes to setting up an interplanetary intercept.  Can't seem to quite nail it perfectly (my orbit relative to the sun usually is a little ways past the target planet).  That said, I seem to have had more issues with the predictions being inaccurate, or outright changing when I'm not looking.

Ever had it happen?  Come back to a ship in-transit which you left with a great intercept and a finely tuned periapse after your last correction burn, shut down for the night or go do some other mission in the meantime, only to find that craft doesn't have an intercept at all anymore?  I think I've read it's sortof the losses between keplerian on-rails physics and newtonian physics when you're actually doing stuff with the craft.  Anyone know how to minimize this?

[SSgt Baloo]

I have found that using Mechjeb, I can just click on the desired planet or moon (as long as my vessel is in the same SOI as the target), then halt execution when it plots the intercept. I then edit the node by dialing back the Δv until the periapse at the target is high enough that I'm confident I won't be colliding with terrain when I get there. Then I execute the node, and can circularize once I'm in the target planet/moon's SOI, usually at the periapse, or some altitude I'll be passing through on my way to it, if that's too low for me.

If I have about ten minutes before node arrival, even my shaky hands have time to adjust the node until it's going where I wanted.

Edited April 4, 2016 by SSgt Baloo
Forgot to delete the quote box I somehow managed to type the above message in..

[triffid_hunter]

 

On 23/3/2016 at 1:26 AM, zarakon said:

This is one of the things that I find really lacking in the stock game.  There's no straightforward way to find interplanetary transfer windows without using a mod or external calculator.

Actually there is - Maneuver nodes!

First get into LKO, then set up a maneuver node that barely escapes Kerbin's SOI in the direction of kerbin's travel (for outer planets) or in reverse direction (for inner planets).

Then create a second node in Kerbol's SOI to intercept the target's orbit, and drag it around to find your intercept.

DO NOT EXECUTE THESE NODES - instead, wait until *kerbin itself* is at the position of the second node, then delete both nodes and construct a new one to burn straight from LKO.

I made a video about it: