This isn’t tool related, but…
Kerbal Space Program is an awesome game. I have been too busy to play it, but maybe telling you about it will help me feel better about this. There’s a free demo if you’d like to give it a go without committing to a purchase.
I played the demo, got frustrated with it, played it again after a few months, and then bought the full version for $40 via Steam.
If you get stuck, look for Scott Manley’s tutorials, or play the in-game ones.
Once you’re ready to take things to the next level, download and install the free Kerbal Engineer Redux add-on, or MechJeb. I like Kerbal Engineer because it gives you all sorts of information without handling the flying for you.
Kerbal Engineer Redux is really needed if you want to do anything more than reach a stable orbit.
I haven’t touched the game in a few months, but the last time I played, I was done visiting both local moons and was building a multi-part space station in Kerbal orbit for refueling my first interplanetary landing craft.
I’m going to be honest with you – Kerbal Space Program is NOT for the impatient, but can very rewarding – more so than shooting monsters or baddies in the face in your favorite first person shooter game.
I have had to whip out a calculator, refer to dV subway-style maps, and I spent more time on Wikipedia and the web learning about orbital mechanics than I’d like to admit.
The deeper you get into the game, the more you’ll learn. Even if you don’t delve into tutorials or how to’s, and simply learn as you go, Kerbal Space Engineer will teach you a lot of sophisticated physics and engineering concepts.
At its core, it’s a really, really fun game.
But be warned, it also has its frustrations. For me, one of the best and worst parts of the game was accidentally getting the lead Kerbal character stuck in solar orbit, before I unlocked maneuvering nodes. It took a lot of reloads and some cursing to get him back home safely.
I suppose you could simply call it a spaceflight simulator. If you think that’ll interest you, download the free demo and take it for a spin.
I bought my copy from Steam, at its full retail price($40). At the time of this posting, it was on sale for $24.