Swallowed by KSP like a supermassive black hole does it with, you know, everything

[papics]

Hi everyone,

I am new here, found KSP from the latest xkcd reference, and after trying the demo, immediately bought the full version So far I have put a probe on Mun and started building a space station around our home planet (with a docking taking way too long caused by a lack of properly placed small thrusters... next time I will add a few more of those tiny little bastards), and I do not see the end of it coming soon Also, having a PhD in astronomy and astrophysics does not mean I have not crashed a few test-flights before I restarted the game and took everything a bit more seriously (using TWR, I_Sp, and deltaV calculations: what a nerdgasm ). It is the coolest game I have played in a while, so thanks to the community and I am looking forward to the evolution of the game in the near future!

To infinity and beyond!

[Monkeh]

Hi, wave good bye to your social life. That Mun base won't build itself you know.

Can I recommend the Kerbal Engineer Redux mod that saves you having to do calculations yourself? I mean, I wouldn't want to take your nerdgasms away, but it does make life a lot easier.

Anyway, have fun around infinity, it never seems to end you know.

[papics]

Thanks for the link, but at this point I am trying to avoid mods and do everything without them It's just the pure philosophy. And, BTW, manually calculating stuff adds an extra pinch of wonder to the experience Ok, maybe when I arrive to the stage of using really complicated rocket-monsters, then I will get such a mod for the calculations...

[Vanamonde]

having a PhD in astronomy and astrophysics

Can you explain the Oberth effect to me in terms of the forces involved but without the math? Because the momentum equations don't tell me what's happening in a way I can visualize. Also, gyroscopes: 1) black magic, 2) or what?

[Tw1]

Swallowed by KSP like a supermassive black hole does it with, you know, everything

Welcome to the club!

[DaRocketCat]

Also, gyroscopes: 1) black magic, 2) or what?

Obviously black magic.

Also, is the oberth effect simulated in KSP?

Edited August 6, 2013 by DaRocketCat

[DaRocketCat]

sorry accidently made a double

[Specialist290]

Can you explain the Oberth effect to me in terms of the forces involved but without the math? Because the momentum equations don't tell me what's happening in a way I can visualize.

Not the OP or a guy with a PhD myself, but I do have a Robert Heinlein quote that might be useful:

A gravity-well maneuver involves what appears to be a contradiction in the law of conservation of energy. A ship leaving the Moon or a space station for some distant planet can go faster on less fuel by dropping first toward Earth, then performing her principal acceleration while as close to Earth as possible. To be sure, a ship gains kinetic energy (speed) in falling towards Earth, but one would expect that she would lose exactly the same amount of kinetic energy as she coasted away from Earth.

The trick lies in the fact that the reactive mass or 'fuel' is itself mass and as such has potential energy of position when the ship leaves the Moon. The reactive mass used in accelerating near Earth (that is to say, at the bottom of the gravity well) has lost its energy of position by falling down the gravity well. That energy has to go somewhere, and so it does - into the ship, as kinetic energy. The ship ends up going faster for the same force and duration of thrust than she possibly could by departing directly from the Moon or from a space station. The mathematics of this is somewhat baffling - but it works.

But yes, gyroscopes do seem to run on mystical and arcane forces for me, too.

[papics]

Can you explain the Oberth effect to me in terms of the forces involved but without the math? Because the momentum equations don't tell me what's happening in a way I can visualize. Also, gyroscopes: 1) black magic, 2) or what?

Unluckily, celestial mechanics and rocket science was not my speciality (if you are curious, it was asteroseismology), so nope, I can not explain that, I am not even sure I know what is that But gyroscopes are cool, they are not black magic at all! I think the wiki article here https://en.wikipedia.org/wiki/Reaction_wheel explains it pretty well. The only problem with them: usually the first part to fail in a space mission, since it is constantly under changing forces (torques, friction, etc.), so they usually put spare ones on (min. 3 is needed for a stable flight), or replace them (e.g., during some of the Hubble Repair Missions).

[wasmic]

That quote... it makes so much sense! I finally understand the Oberth Effect! HELL YEAH!

Oh, and @papics, you're really missing out by not using mods. It might be smart to only use stock in the beginning, but after a while, reconsider adding mods. Maybe a pack like KW or NovaPunch - they are quite well balanced against stock. Maybe you'd want to try something completely different and use Ioncross crew support mod, or the deadly re-entry mod. Maybe you'd start a colony on duna with BobCat's H.O.M.E. pack? Mods are, as far as I know, a quite big contribution to KSP's success as a game.

[papics]

I know, but for now, till I get a fellow Kerbonaut to every planet and moon of the Kerbol system, I will stick to stock Then I am sure I will open up towards the mods!

PS.: four hours of game time after work today (girlfriend having a girls' night out), another module docked to my space station (but I again forgot to put floodlights on...), first EVA around the station, then a lander sent to Minmus! So cool!!!

[little square dot]

Mods are, as far as I know, a quite big contribution to KSP's success as a game.

I have two installations, modded and non, and I can honestly say that neither way of playing is better than the other.

Playing stock is much more challenging, and having to improvise with the stock parts is a heck of a lot of fun... the ghastly looking frankenships that one inevitably creates are pretty hilarious.

That said, the stock game feels rather lifeless, and the severely limited selection of parts can become quite annoying, which is where mods come in.

I have been absolutely amazed by the quality of most of the mods this community has churned-out, and there are plenty of game-enhancing mods that don't detract from the stock game in any way(ISA MapSat, Remotetech, KAS, Chatterer, Crew Manifest, etc, etc, etc.).

Of course, once one begins to add mods to KSP, one has trouble knowing where to draw the line, often resulting in the game becoming less challenging, unstable(those delightful out-of-memory crashes!), and sometimes even overwhelming(TOO MANY OPTIONS!!).

Also, the persistent save files of heavily modded games aren't always easily transferred to new versions of KSP, leading to many fresh starts.

Depending on the person, this isn't necessarily a bad thing.

Anyway, tomato, tomato... erm... I guess that doesn't translate well through text. Tomato, tomaaato?

(welcome aboard papics=)

[Space Ace]

Well some Mods are great fun to play with and they don't break the stock feeling of the game by that much.

But some things I would hate to miss.

It is a good policy though to try something without aid first.

Made my first rendevouz and docking procedure without any aids, now when I assemble things made from a multitude of parts I'd rather have a Rendevouz Autopilot and a Docking Camera handy. I still do the docking myself.

Also I can't rely on any computer to get my insane creations safely into orbit

[Vanamonde]

Another stock player here. I just find it more interesting to see what I can do with the basic stuff.

On the Oberth effect, so the system of the ship-and-fuel doesn't gain anything by falling into the gravity well, but after the fuel is ejected as exhaust, the ship retains the momentum the fuel gained during the fall?

[Tw1]

But yes, gyroscopes do seem to run on mystical and arcane forces for me, too.

I've heard gyroscopes described in terms of angular momentum and inertia.

The faster something's going, the more energy it takes to divert it from its course.

The parts of the gyro wheel are moving fast in a circular motion. The faster it's going, the more energy is needed to change the angle of the gyro, because that's changing the paths of the parts of the wheel.

This was a simplification, so what's really going on must be more complex than that.

[Diche Bach]

Welcome Papics! I too am a relative newcomer, although verbose. Don't let that post count fool ya; with a Ph.D. in anthropology, I know even LESS about gravity wells and such than you do! Nonetheless I have managed to do a couple successful "sling shot" maneuvers around the Mun.

I played with Stock for about 90 hours of play, and then it just seemed time to add the mods. Can share my list of which ones I thought looked good when you are ready.

[zxczxczbfg]

I recommend that, when you get around to modding, install MechJeb to simulate mission control and/or slide rules. It drastically cuts down on the number of missed transfers because of an accidental mid-burn spin, as well as cutting down on the tedium of manual docking with its docking autopilot.

[Specialist290]

On the Oberth effect, so the system of the ship-and-fuel doesn't gain anything by falling into the gravity well, but after the fuel is ejected as exhaust, the ship retains the momentum the fuel gained during the fall?

Essentially, yes. The total energy of the system is conserved, relative to the planet. What's happening is that, by Newton's Third Law, the force acting on your rocket when you burn your engines also acts on your propellant with an equal amount of force along the opposite vector.

As usual, I've managed to dig up a link that I think explains the details a little better than I ever could.

@Tw1: I guess I'll have to do a little more digging to understand it fully, but that information's certainly a helpful start. Thanks!

[papics]

I have two installations, modded and non, and I can honestly say that neither way of playing is better than the other.

This seems like a nice intermediate option, I would have never thought about that! I might give it a try!

[DaRocketCat]

You should definitely use Ferram Aerospace Research, it offers much improved aerodynamics.

[Capt'n Skunky]

Happy Launching!

Arrr!

Capt'n Skunky

KSP Community Manager