Race to Proxima Centauri

[MeticulousMitch]

Race to Proxima Centauri

For version 0.17

Let's assume for a moment that the Kerbol system is an analogue of our own solar system, and that corresponding star systems exist outside it.

Your challenge is to reach Proxima Centauri, the nearest star at a distance of 4.24 light years, as fast as possible. So how do you do this?

First you need to escape from the sun, that is (for the purposes of this challenge) achieve a distance of 1 Billion Km, and then record your velocity. Then use that velocity to calculate your travel time to Proxima Centauri.

I'll kick off this challenge by posting my first attempt:

Velocity at sun escape: 29.307 km/s

Distance to Proxima Centauri: 4.011x10^13 km

(4.011x10^13km) / (29.307km/s) = 1.3687x10^12 seconds = 43,402.14 years.

I personally only fly stock craft, but I'm quite interested to see what times you can achieve with mods, so I've made two categories.

Challenge Leaderboard:

Stock:

1.) Max Schram - 22,214 years

2.) Bluejayek - 25,330 years

3.) maltesh - 26,681 years

4.) Andydouble07 - 38,222 years

5.) MeticulousMitch - 43,402 years

Mods:

1.) - 1of6Billion - 2,515 years

2.) -Hammer Bridges - 2,721 years

3.) - Mars9000000000 - 19,740 years

4.) - maltesh - 25,931 years

5.) -

You can of course use any craft you like, but if you want to try mine or improve on it, the file is attached below.

Edited October 15, 2012 by MeticulousMitch

[iplop]

Oops, I left my PC for a while and accidentally missed my mark. I came back at 1,374G.

Ship: [ATTACH]33742[/ATTACH] (stock)

Edited September 27, 2012 by iplop

[The Destroyer]

Huh, Interesting. Might do it.

[Bluejayek]

Well, I am attempting this, unfortunately what keeps happening is:

[Bluejayek]

65,318 years

[MeticulousMitch]

65,318 years

Thanks for playing Bluejayek! That must be an insanely powerful ship - from the looks of the mission timer it appears you didn't even use a sun slingshot manoeuvre (because that takes quite a while). Any chance of seeing the full ship on the pad?

[untitled]

6 billion.

http://imgur.com/fP5ME,4E14y

If I remember correctly though, my perigee speed was something ridiculous in the range of 20k-30k m/s (perigee was at 13 million km)

[phoenix_ca]

Does the craft need to be capable of lifting itself off the launch pad? Realistically-speaking, it shouldn't (I don't think even Kerbals would be so dumb as to try such a thing). And if it's a "problem" one could toss it into the mods category (which I certainly wouldn't mind since I'm going to happily use a bunch of mods to go as fast as possible).

Still, love the idea. Will give me motivation to do something after having just accidentally wiped-out my save-data. (Word of warning, be VERY careful when deleting your saves from the in-game menu. O.O )

[MeticulousMitch]

Hi Phoenix_ca, that sounds fine to me but I think I'll have to stick it in the mods category. Looking forward to seeing your entry!

[djnekkid]

Not to be a nitpicker, but would not Proxima Kentauri be more or less 0,4ly from Kerbol? As everything in the KSP-universe is scaled down about an elevenfold?

Earth:

Equator radi: 6378km

Semi-major axis: 1.0 AU

Kerbin:

Equator radi: 600km

Semi-major axis: 0.09AU

Jupiter

Equator radi: 69,911km

Semi-major axis: 5,2AU

Jool

Equator radi: 6000km

Semi-major axis: 0.46AU

Mars

Equator radi: 3400km

Semi-major axis: 1,52AU

Duna

Equator radi: 320km

Semi-major axis: 0.13AU

[MeticulousMitch]

Not to be a nitpicker, but would not Proxima Kentauri be more or less 0,4ly from Kerbol? As everything in the KSP-universe is scaled down about an elevenfold?

Feel free to divide the travel times by 11 if you wish, but this challenge is really about velocity. Listing results as absurdly long travel times was my attempt at putting the vastness of space into humorous perspective, and give us some concept of just how far away the REAL Proxima Centauri is.

Thanks to the three who have attempted this already - keep 'em coming folks!

Edited September 28, 2012 by MeticulousMitch

[phoenix_ca]

Hi Phoenix_ca, that sounds fine to me but I think I'll have to stick it in the mods category. Looking forward to seeing your entry!

That's fine. The whole thing is modded parts, struts and all. (Except for...nope, all mod parts.) It wouldn't be fair to compare it to stock.

Now if only I could get the darn thing into space without messing-up the staging. >.<

[Bluejayek]

That 29,000m/s score is incredible, I don't know how you managed this. My latest entry had 28,000L of fuel on top of a nuclear engine (Over five hours of burn time) from kerbin orbit out, and still only made 24,000 or so...

[thatgiantsnake]

huh intresting im shooting a rocket out of the solar system at about 370 km/s and i just passed duna's orbit

[Bluejayek]

I tried using the craft file you gave, and I didnt get anywhere near your velocity.

I got 120,660 years with a straight out trajectory.

How did you get the 43,402years figure? Some sort of Jool slingshot?

[MeticulousMitch]

Bluejayek, you can actually get huge increases in velocity by diving close to the sun and accelerating at the periapsis. I reckon your rocket would smoke mine if you did that!

[bradley101]

Useing Mods Could We try to achvie it in a persons life span?

[maltesh]

Bluejayek, you can actually get huge increases in velocity by diving close to the sun and accelerating at the periapsis. I reckon your rocket would smoke mine if you did that!

Indeed. Bi-Elliptic Sundive followed by gravitational slingshot at under 100km from the solar surface. I'd tried a couple times to do this before the Kraken was slain.

This is the Sunrunner. Mechjebbed, but all else is stock. [ Edit: Apparently wasn't stock, accidentally used one double-fuel tank.. See post later in thread. Requesting disqualification]

Sadly, I didn't get any pictures of it on launch, because it was a fickle beastie to get into orbit, and had to restart about a half dozen times. THe lifter stage is asparagus-stalk staged, and yes, I did use Mechjeb, because keeping the ship aimed for 30 minutes during the eventual slingshot was not high on my priorities list.

The orbit stage has six pairs of two-400-unit drop tanks arrayed around a central stack of two 400-unit drop tanks, powered by a nuclear thermal engine. It took four of those tanks to get from orbit to push my apoapsis out to 131Gm.

600 days later, At apoapsis, I then dropped the periapsis to about 100 km over the sun, though I had to do a bit of a plane-change as well to avoid sweeping through Jool's SOI.

Then another 600 days back to Periapsis.

At burnout, top speed was 98.4 km/s.

And of that, 49048.8 m/s remained at 1TM.

I was kind of hoping to get above 50km/s hyperbolic excess velocity, but wobbly steering on launch and the need to avoid Jool's SOI on descent probably were what prevented that.

At any rate, that's a time of 29,215 years.

Edited September 30, 2012 by maltesh

[MeticulousMitch]

And of that, 49048.8 m/s remained at 1TM.

Straight to the top of the leaderboard for you! Fantastic score, well done!

Useing Mods Could We try to achvie it in a persons life span?

You're welcome to use mods, in fact since we don't yet have any modded entries I'd encourage it.

huh intresting im shooting a rocket out of the solar system at about 370 km/s and i just passed duna's orbit

Pics or it didn't happen

[Bluejayek]

Ok, thanks for the tips. I'm going to try again with my rocket using the sundive, the only issue is that even on 4x time warp burning that much fuel on a nuclear engine takes ages

I wonder if this will actually work with the tiny acceleration my ship gets though. How long do you actually have at periapsis to burn?

[Bluejayek]

I claim victory.

25,330 years.

1424.3 tons on launchpad.

The sundive move gives an enormous boost. I had to start my burn an hour and a half before periapsis, so I was over 100,000km at the start, but it still more then doubled my speed.

By the way, while doing this, did you guys notice a much diminished version of the kraken when going absurdly fast?

Edited September 29, 2012 by Bluejayek

[maltesh]

Straight to the top of the leaderboard for you! Fantastic score, well done!

Thanks, but I'm afraid I'm going to have to request my own disqualification.

Several days ago, I wound up making a second standard-sized liquid fuel tank, and doubled the number of fuel points in it so try to see if specific-impulse-based engines got their burn time directly from the empty and dry mass values in the .cfg file, or if they got it from some vague consistency with the liters value that you get when you right-click on a fuel tank.

And like an idiot, I didn't give the modified fuel tank an obvious garish color to make it obvious to me that it was a modified fuel tank. I normally do that, but for some reason I didn't.

So when I built the Sunrunner, the tank just under the pod wound up being a fuelTankBLARR instead of a fuelTank. I didn't notice this until I was checking the persistence file this morning.

And as a result, in the middle of the powered slingshot, when the spacecraft was nearly the lightest it would get, it was burning a tank that had twice the fuel capacity it should have had, resulting in a higher velocity at 1Tm than it should have had. How much higher is an interesting question, I'd guess possibly as much as a dozen km/s.

So, yeah. Definitely wasn't stock. I'll probably throw out another submission with truly stock + mechjeb parts in a few days.

[Bluejayek]

And as a result, in the middle of the powered slingshot, when the spacecraft was nearly the lightest it would get, it was burning a tank that had twice the fuel capacity it should have had, resulting in a higher velocity at 1Tm than it should have had. How much higher is an interesting question, I'd guess possibly as much as a dozen km/s.

.

Hmm, that does explain a few things. I had wondered how your velocity was so close to mine with only 1/5th of my fuel; I had put it down to more efficient staging (your effective payload mass is like 1/4 or 1/5th of mine) and a final burn closer to periapsis. I would be interested to see what you get if you use that ship as pure stock.

Either way, it is a nice entry, and he should just bump it over to the modded leaderboard.

Edited September 30, 2012 by Bluejayek

[iplop]

Second attempt:

[maltesh]

Hmm, that does explain a few things. I had wondered how your velocity was so close to mine with only 1/5th of my fuel; I had put it down to more efficient staging (your effective payload mass is like 1/4 or 1/5th of mine) and a final burn closer to periapsis. I would be interested to see what you get if you use that ship as pure stock.

Either way, it is a nice entry, and he should just bump it over to the modded leaderboard.

Well, I put a regular fuel tank into the Sunrunner3 and made a couple more modifications:

Found the strut that was snapping on launch, which prevented the ascent corkscrewing.

This meant the last stage of the lifter could be used to help throw Sunrunner 3 to my traditional 131Gm Bi-elliptic sundive distance.

Jool and all the other planets were well out of the way this time, so I didn't have to spend any more delta-V avoiding them, and I went for a periapsis at a mere 13 km over the solar sutface.

Maximum velocity was just under 98 km/s achieved at an altitude of about 55,000 km over the solar surface.

47670.2 m/s of that was carried out to 1Tm, for a time of 26 663.1 years. Guess that bad luck and poor building made the original Sunrunner fly suboptimally, even though it had that modded fuel tank.

Sunrunner 3.craft - Mechjebbed, rest stock.