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Comment by Andrew_nenakhov | Hacker News Reader

Oh, fond memories of it. It was the first time when I understood that when you fly to the Moon, not only you have to cross the Moon's orbit, but you have to do it when Moon itself is nearby. If you are 1/4 orbital period ahead of it, you are screwed.

It also ruined space movies like "Gravity" for me, because pointing the nose to the space station in 50 km and applying thrust towards it turns out to be a sure way to NOT get to that station!

Edit: fixed the thrust direction

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I first discovered this game back in school at around 2010-2011 and it quickly turned into one of the defining games of my childhood. I wish I had some numbers but I am certain that I played hundreds of hours playing this game, installing countless mods, learning orbital dynamics, spaceflight history, and so much more. I flew to mars and back, landed on the moon, programmed flight computers (sometime catastrophically wrong), docked so many different vehicles in orbit and generally had the time of my life in this game. Dan's Orbiterpage and his world class mods for the game (including the excellent sound mod) really made this game (or sim, whatever you call it) shine. I probably also spent days of my life browsing orbithangar for the coolest new vehicles.

At some point I discovered Kerbal Space Program and eventually got older and had less time for Space Sims altogether, but Orbiter (especially the 2010P1 version) will remain closest to my heart.

I am really happy to see this game become open source.

I had a similar experience when playing Kerbal for the first time in high school. I thought that NASA got to the moon by simply thrusting in a straight line from Earth in a way that would intersect with the moon's orbit and boy was I wrong!

But now I've found that most people I talk to about this — that also weren't alive during the space race where this was regularly explained on television — have the same naive idea that you can get to the moon by going straight up at it with the right timing.

Instead, you learn that you need to enter orbit and burn prograde at your apoapsis, burn retrograde at the moon's periapsis, etc. — really fascinating and complex stuff! If the curriculum would've allowed it, I feel like I could've spent a whole semester playing and learning from KSP — these kind of games are truly the top of "games for learning" genre.

Yes, the key here is to understand that you are not exactly flying, but always falling towards something, and you need to change the trajectory of your fall to get anywhere.

So space flight is much closer to sky diving than to air flight.

That's actually the easiest way to get to the Mun in my opinion. No need to plan anything anything just shoot straight up. If you don't get an orbital encounter initially just keep shooting up until you do, it'll happen many times before you reach Kerbin Escape velocity. No need to time anything or plan certain maneuvers.

Basically shoot upwards until you get an encounter, speed up until it auto slows you down near the Mun, then kill velocity to fall in and land.

Grossly and hilariously inefficient but actually easier to perform than the "correct" way (and typically faster in player-time).

Yeah! This was another great realization from KSP — figuring out that the naive way is possible, but the delta V required to do it is absurd.

Here's a video of a KSP speed-run to the Mun and back in 2 hours using this method (with 10K m/s total delta V — I think Jeb takes 34Gs at some point, which is about 5-10x what normal astronauts feel): https://youtu.be/0dx7ScJSAwo

That is only possible if you have engines and fuel capable of sustaining a powered flight. We puny humans so far don't have it.

You don't need to sustain thrust the entire time you just need to reach a significant portion of escape velocity energy early in your launch (which is what most launches need anyways just this time you need slightly more energy than the efficient way). This is not something we have trouble doing, for reference we launched New Horizons directly into above escape velocity speed with an Atlas V rocket. The only reason we haven't done that kind of launch to the moon in real life is it's far cheaper and more efficient to do that "normally" not because we couldn't.

Nah the easiest way is just to get in low kerbin orbit, timewarp until you see the mun come over the horizon, then burn prograde. No manouver nodes necessary.

I love KSP. No other videogame has given me such a sense of Pride and Accomplishment™.

I was once asked to describe KSP and the best answer I could come up with is: "It's a game about speeding up and slowing down".

Even just knowing basic physics ruined Gravity for me, let alone orbital dynamics.

The most unrealistic part of Gravity isn't the orbital mechanics, it's the part where she gets out of a spacesuit without assistance from others in 10 seconds flat.

I think you meant to say "pointing the nose to the space station in 50 km and applying thrust towards it turns out to be a sure way to NOT get to that station"

Edited: made mistake as well ;)

Yeah, my bad english. Used word 'thrust' to describe a burn in the opposite direction, totally forgetting that thrust is a reactionary force. :-/

Ah, I see. Not so sure myself now.

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