Kerbin Versus Earth: A visual comparison

[jaredkzr]

Let's give the credit to the guy who made this. The original link is here: http://www.reddit.com/r/KerbalSpaceProgram/comments/1k9o89/i_was_inspired_to_make_kerbin_vs_earth_a_visual/

[-RanZ-]

pretty sweet

[razark]

Aircraft pilots still use slide rules

They're about the only ones that do on a regular basis, but an E6B is kinda limited in what it does. (Not that it's not great at what it does, it's just great at a very limited set of tasks.)

Now I'm wondering how useful it could be in KSP.

[lincourtl]

That quote at the end..was that Jules Verne?

It's from a sonnet by John Gillespie Macgee, Jr. dating to 1941 called "High Flight." Most people know it today because it was used in Ronald Reagan's speech following the Challenger disaster.

"High Flight"

Oh! I have slipped the surly bonds of Earth

And danced the skies on laughter-silvered wings;

Sunward I’ve climbed, and joined the tumbling mirth

of sun-split clouds,  and done a hundred things

You have not dreamed of  wheeled and soared and swung

High in the sunlit silence. Hov’ring there,

I’ve chased the shouting wind along, and flung

My eager craft through footless halls of air....

Up, up the long, delirious, burning blue

I’ve topped the wind-swept heights with easy grace.

Where never lark, or even eagle flew â€â€

And, while with silent, lifting mind I've trod

The high untrespassed sanctity of space,

- Put out my hand, and touched the face of God.

[Crown]

[Akinesis]

I looked at the OP's link yesterday, and again today. I cannot believe how small Kerbin is to Earth. I knew it was smaller... but THAT small!

Great stuff!

[Kerbart]

[...]But i do feel it kinda does miss the point of what KSP learns the players. It educates us in the basics of orbital mechanics and not so much the engineering tasks..[...]

As a game, there's a lot more where KSP differs from reality and that's just fine. In any area where your expertise is you will found glaring errors, and thank goodness for them because the game would be a lot less fun if it were not realistic:

• Orbital Mechanics: stable orbits, no n-body calculations. No tidal effects. There's a lot about orbital mechanics that is missing
  
• Engineering: you mentioned those. Yes, in reality you don't put a spaceship together like lego's. Once career mode is there it'd be really cool to have a choice between similar components (performance wise) that are either cheap or reliable. It's not like Kerbal players mind seeing things getting blown to pieces at launch time, after all.
  
• Psychology/Kerbal Resources: "Halfway during the 2-year trip to Jool, Bill Kernam screamed 'I can't take this ever smiling maniac anymore' and dived at Jebediah, pummeling him with his flag pole." There's not screening of new kerbonauts to see if they can deal with being in close quarters with their fellow kerbonauts for a long time. Maybe they don't have these problems? But it's definitely a lot simpler than in human spaceflight. Not to mention that recruiting a new kerbonaut is literally a matter of picking them off from the street, and they're ready to go for a three or four year mission to the outer planets...
  
• Mission control: it's cool that you're instructing Jebediah to avoid a crash on the surface of Bop that's about to happen. BUT YOU DO REALIZE THAT THE CRASH WAS "IMPENDING" TWO MINUTES AGO, RIGHT". Luckily you don't have to deal with "signal travel time" in KSP...
  

There's lots of simplifications in KSP, and all for the better of it, it makes it a fun game to play. And KSP might teach more about orbital mechanics than about rocket ship design. But I don't think you have to be afraid that one particular area has been "left out" when it comes to (the lack of) realism over the other--sacrifices have been made everywhere!

[hugix]

As a game, there's a lot more where KSP differs from reality and that's just fine. In any area where your expertise is you will found glaring errors, and thank goodness for them because the game would be a lot less fun if it were not realistic:

• Orbital Mechanics: stable orbits, no n-body calculations. No tidal effects. There's a lot about orbital mechanics that is missing
  
• Engineering: you mentioned those. Yes, in reality you don't put a spaceship together like lego's. Once career mode is there it'd be really cool to have a choice between similar components (performance wise) that are either cheap or reliable. It's not like Kerbal players mind seeing things getting blown to pieces at launch time, after all.
  
• Psychology/Kerbal Resources: "Halfway during the 2-year trip to Jool, Bill Kernam screamed 'I can't take this ever smiling maniac anymore' and dived at Jebediah, pummeling him with his flag pole." There's not screening of new kerbonauts to see if they can deal with being in close quarters with their fellow kerbonauts for a long time. Maybe they don't have these problems? But it's definitely a lot simpler than in human spaceflight. Not to mention that recruiting a new kerbonaut is literally a matter of picking them off from the street, and they're ready to go for a three or four year mission to the outer planets...
  
• Mission control: it's cool that you're instructing Jebediah to avoid a crash on the surface of Bop that's about to happen. BUT YOU DO REALIZE THAT THE CRASH WAS "IMPENDING" TWO MINUTES AGO, RIGHT". Luckily you don't have to deal with "signal travel time" in KSP...
  

There's lots of simplifications in KSP, and all for the better of it, it makes it a fun game to play. And KSP might teach more about orbital mechanics than about rocket ship design. But I don't think you have to be afraid that one particular area has been "left out" when it comes to (the lack of) realism over the other--sacrifices have been made everywhere!

Exactly my point. KSP is a fun game that teaches you the very first steps into orbital mechanics in a very fun to play way. If KSP was more like the real life thingies in the picture it would make the learning curve even more difficult. It takes the best out of both worlds (simulator and game)

[Diche Bach]

Second time I've seen that DeGrasse Tyson video linked here on KSP forums and this time it actually made me tear up watching it. His message is so sincere, so true, so important. "Broke!" indeed . . .

It breaks the heart to realize where we are now and the path we seem locked into thanks in large part to lack of real leadership at any level in our society. DeGrasse Tyson is to be applauded for expecting better and expressing it with such passion and precision.

If each of us goes about our daily lives with even a small fraction of his passion, perhaps cumulatively we can help to catalyze change.

[AncientAstronaut]

To the OP: great stuff!

I was tempted to make a joke about Apollo being a big hoax, but ah. Out of character, and probably not the most strategic moment to tickle that particular funny bone.

Not out of character. Everyone knows Apollo was a hoax... It doesn't take much Delta-V to get to a studio set.

INB4 PEOPLE THINK I'M SERIOUS.

[zarakon]

Has anyone made KSP mods to change the scales to match real life? Earth-sized Kerbin, Moon-sized Mun, etc. as well as larger engines and fuel tanks with higher T/W ratios and better fuel mass fractions?

Seems like it would be fun to try out

[Geschosskopf]

Second time I've seen that DeGrasse Tyson video linked here on KSP forums and this time it actually made me tear up watching it. His message is so sincere, so true, so important. "Broke!" indeed . . .

It breaks the heart to realize where we are now and the path we seem locked into thanks in large part to lack of real leadership at any level in our society. DeGrasse Tyson is to be applauded for expecting better and expressing it with such passion and precision.

If each of us goes about our daily lives with even a small fraction of his passion, perhaps cumulatively we can help to catalyze change.

Um, well..... (see below)

Has anyone made KSP mods to change the scales to match real life? Earth-sized Kerbin, Moon-sized Mun, etc. as well as larger engines and fuel tanks with higher T/W ratios and better fuel mass fractions?

Seems like it would be fun to try out

There's a game already that does this. It's called "Orbiter". I've played it off and on since the 1st version came out way back in the late 80s IIRC. I'll never touch it again now that I have KSP. Orbiter is interesting, but extremely un-fun when you get right down to it, at least compared to KSP. But Orbiter is very good for 1 thing, and that's showing you exactly why we quit sending people to space, and why there's no hope of ever doing so on a large enough scale to matter a bit with even realistically foreseeable future technology.

So I disagree with Mr. Tyson. I haven't stopped dreaming. I play a lot of KSP, after all. But that's where do my dreaming now. Dreaming about doing anything similar in real life is as pointless as sending a handful of people somewhere just to plant a flag.

[zarakon]

There's a game already that does this. It's called "Orbiter".

The big difference being that you can't just easily build your own rockets in Orbiter, right?

[Diche Bach]

Um, well..... (see below)

There's a game already that does this. It's called "Orbiter". I've played it off and on since the 1st version came out way back in the late 80s IIRC. I'll never touch it again now that I have KSP. Orbiter is interesting, but extremely un-fun when you get right down to it, at least compared to KSP. But Orbiter is very good for 1 thing, and that's showing you exactly why we quit sending people to space, and why there's no hope of ever doing so on a large enough scale to matter a bit with even realistically foreseeable future technology.

So I disagree with Mr. Tyson. I haven't stopped dreaming. I play a lot of KSP, after all. But that's where do my dreaming now. Dreaming about doing anything similar in real life is as pointless as sending a handful of people somewhere just to plant a flag.

That's a non-standard perspective in this crowd! Would agree that there is a lot of dreamy eyed sci-fi inspired BS. But "quit sending people to space, and why there's no hope of ever doing so on a large enough scale to matter a bit," that just doesn't seem accurate at all.

In the first place there have been humans in space pretty much continuously for the past 15 or 20 years (Mir and ISS). Also the idea of what matters would seem to be pretty subjective.

[samstarman5]

Well, it helps that we don't have super-dense materials here on Earth like they do on Kerbin. When you actually scale things up to account for that, Kerbals do have an easier time than us, but not quite as much so as that chart makes it seem. It was more than a bit unfair to compare a 1-Kerbal minimalist lander to the 2-man decidedly-not-minimalist Apollo lander, also.

Bear in mind the Lunar Lander is mostly tinfoil, allowing for a much lighter module. In ratio, the tuna can is much heavier. In some ways, we have to work harder for extra-Kerbin landings than NASA does. We are the stronger force for space.

[paleorob]

Best comment: "irl lol at SI-C = 64x Jumbo 64 + 26 Mainsails. I know what I'm building tonight!"

[ledogen]

Lets not forget, though. KSP is a magnificent game, and most of all, a GAME. If all games were super realistic then they'd be boring. Kerbal is a magnificent way to get players involved, without making them frustrated

[Geschosskopf]

That's a non-standard perspective in this crowd!

I'm coming to realize this myself . I grew up during the Space Race so as a child I fully expected to go to Jupiter when I was grown (Mars having been settled in the meantime). But watching the Voyager missions unfold throughout my teens, coming to understand why it took years to get between planets and why the probes couldn't stop at any of them, gradually convinced me, along with starting college in aerospace engineering, of our inability to do much more than that. Then I married a rocket scientist with an obsession about going to Mars, and got even more depressed .

In the first place there have been humans in space pretty much continuously for the past 15 or 20 years (Mir and ISS). Also the idea of what matters would seem to be pretty subjective.

Well, yes, I subjectively think that having a mere handful of non-permanent residents in a non-self-sustaining shanty town in LEO hardly counts as "sending people to space". Now, if we had a number of orbital, self-sufficient cities housing thousands of full-time residents each, THAT would be "sending people to space".

But you can also look at this objectively. With foreseeable technology, we can't do much more than we've already done, mostly because we live at the bottom of the significant gravity well shown in the original post. So what practical benefit accrues back on Earth from doing something like the ISS, or Apollo, or Apollo-on-Mars? Other than the odd new consumer product, nothing. (NOTE: unmanned missions have had real benefits: satellites for weather and communications, for example) And you can't regard any of our manned efforts as 1st steps towards something greater because the gravity well puts such a cap on doing anything on a larger scale with people.

And that's the real pity of it all. I would love to stripmine the Moon for Helium-3 or whatever it is up there that's supposed to be such a great fusion fuel. I would love to export millions of people (especially my ex-wife ) to orbital cities or other planets, both to ease overpopulation on Earth (from which most problems stem) and to have truly viable colonies elsewhere. But until we can get all that stuff off the ground here, none of that is possible. Instead, we're stuck with what we've been doing. So if it was up to me, I would concentrate all space research on finding a way to defeat Earth's gravity well so thoroughly that LEO effectively becomes part of the surface. Then, and only then, can humans do something meaningful in space.

I suppose you can still call this subjective, although I prefer to think it's a realistic assessment .

[NERVAfan]

Eh, there are plenty of ways to accomplish way more in space than we have so far. The problem isn't technology, it's politics.

IF SpaceX's reusability works out, launch costs will probably drop enough in the next decade to start seeing major space projects happening.

If the US devoted, say, 10% of its budget to colonizing space, we would have colonies on Mars and the Moon by now. It's not beyond our technology at all, just expensive.

[hugix]

Eh, there are plenty of ways to accomplish way more in space than we have so far. The problem isn't technology, it's politics.

IF SpaceX's reusability works out, launch costs will probably drop enough in the next decade to start seeing major space projects happening.

If the US devoted, say, 10% of its budget to colonizing space, we would have colonies on Mars and the Moon by now. It's not beyond our technology at all, just expensive.

but even then it is a market build around Lower Earth orbit. There are no profitable business plans thinkable that involve Mars or anything other.

[Whackjob]

I am... hrm... extremely interested in making an actual Saturn V. To spec, per that image. Like stage one being 67 Rockomax 64s, 26 mainsail engines, et cetera.

It'd look nothing like the actual thing, of course, but it might be fun.

#EDIT: Coffee made, firing up KSP now. Wish me luck.

Edited August 17, 2013 by Whackjob

[NERVAfan]

There are no profitable business plans thinkable that involve Mars or anything other.

Sure there are!

Probably not with current launch costs, but with 10x lower (which SpaceX might well be able to achieve quite soon), yes. There's no way to make profits mining Mars or the Moon and shipping the products to Earth (near-earth asteroids, maybe*), but there are lots of other possibilities.

MarsOne is planning to do a colony on Mars funded by media profits - primarily a TV show. I don't at all believe this can work by the timeline they state (first human landing 2023), but if SpaceX's reusability works as well and lowers costs as well as hoped, it should be able to work once those lowered costs are established.

There are all sorts of similar possibilities. Sarah Brightman is supposed to perform from the ISS in a couple years, be interesting to see how much of a splash that makes (yes it's LEO, but in the general "space media" field, still relevant)...

And if SpaceX's stuff doesn't work out, I believe Blue Origin is working on similar stuff (not nearly so far along), and Reaction Engines Limited thinks they can make the SABRE engine that allows Skylon - a single-stage-to-orbit spaceplane that is also supposed to drastically lower launch costs (though that one's not very far along at all, they haven't made a complete engine much less a vehicle).

It all depends on launch costs, but I think in the modern world, for media type stuff to be profitable, they don't have to be AS low as many would think.

*If you can find a way to make heat shields from the non-valuable asteroid material, allowing aerobraking, then getting near-earth asteroid materials to Earth has a very low delta-V requirement.

[Tiron]

On the subject of Apollo Hoaxes:

The Mouseover Text: "Ok, so Spirit and Opportunity are pretty awesome. And Kepler. And New Horizons, Cassini, Curiosity, TiME, and Project M. But c'mon, if the Earth were a basketball, in 40 years no human's been more than half an inch from the surface."

[Whackjob]

Quick update:

Bottom stage is holding up well. I'm 2.5 orange tanks off and 1 mainsail engine. I have to split that into two to maintain symmetry. But the core is OK. I'll add those on, then add on the next stage above it.

While I'm putting together this mad bit of kit, can someone dig up the KSP equivalent of thrust and fuel and weight for both the command module and both stages of the lander? I might as well go all out.

#EDIT: Bottom stage done, moving on to intermediary stage! First stage handles like a champ. Interestingly, it has a TWR ratio of less than 2. Like 1.6. That's PRIOR to putting the other stages above it!

Edited August 17, 2013 by Whackjob

[Splode]

As others have pointed out, this is misleading at times. The fuel in KSP is a lot less efficient than actual rocket fuel, and the thrust to weight ratios of real engines (and fuel to weight of tanks) is much higher in real life. Otherwise the game would be too easy! The main reason for the shrinking of everything in KSP is so everything takes less time, rather than to make things easier.

There are things we don't have to deal with in KSP that make life hell for real engineers and scientists, but the underlying physics isn't really one of them.