The KSP Interstellar Proxima Centauri Challenge

[FreeThinker]

4 minutes ago, pmborg said:

Yes that's the pretty thing about "Kit Container", that's why I am using it, I can put over there what ever I want (300 or 600 parts) and will count only with 1 part, until being constructed.

Yes but the kid is pre packaged right, you can no longer change your mind after launch

[pmborg]

3 minutes ago, FreeThinker said:

Yes but the kid is pre packaged right, you can no longer change your mind after launch

Actually with the "Assembly line" we can create a new "Kit Container" and attach a new vessel inside, so yes in the other planet we can create whatever will be needed over there.

• We can't create more Kerbals on the other planet... like we do on KSC by recruiting
• But there is a mod that will simulate child's from Kerbins Civilian Population:

Edited August 15, 2019 by pmborg

[FreeThinker]

I didn't know that, What about recycling?

Edited August 15, 2019 by FreeThinker

[pmborg]

10 minutes ago, FreeThinker said:

I didn't know that, What about recycling?

• That it should be a very good Idea for the "Ground Construction mod"
• Please keep in mind that whatever you want to construct cost resources but resources can be made/farmed

But if it is needed to remove some junk from a remote planet scenery like what I do in a remote planet is remove it! (notepad++)

Edited August 15, 2019 by pmborg

[FreeThinker]

2 hours ago, pmborg said:

• We can't create more Kerbals on the other planet... like we do on KSC by recruiting
• But there is a mod that will simulate child's from Kerbins Civilian Population:

A more recent incarnation might be

Edited August 15, 2019 by FreeThinker

[FreeThinker]

2 hours ago, pmborg said:

But if it is needed to remove some junk from a remote planet scenery like what I do in a remote planet is remove it! (notepad++)

Perhaps its an idea to add more stages:

[pmborg]

8 hours ago, FreeThinker said:

Perhaps its an idea to add more stages:

In theory this is a good idea, but in practice once useful payload is 600tones, I am not sure if the small ones will be efficient to do the work but I can try.

(@FreeThinker), What is the payload and delta-V of this baby here?

Edited August 16, 2019 by pmborg

[pmborg]

• As I suspected, already confirmed don't work, another stage reduce the delta-V from 124.7M to 119M:
•  
• 

Edited August 15, 2019 by pmborg

[pmborg]

First Attempt - Engine Power from Asteroid, I am trying to understand the scale of the drills and ISRU needed.

[pmborg]

Got it (@FreeThinker), there is only one way to do it, I mean make a 3th stage to work, replace 600tones of payload and transform the 600tones in another 3th Stage... of 1850kg of payload that could give

with Daedalus: Another 18.85M delta-V on a total 143.85M delta-V, so that's why in theory work but not in practice, but can give 47.95% speed of light, to send a probe is ok!

with Bussard: Another 43.6M delta-V on a total 168.6M delta-V, so that's why in theory work but not in practice, but can give 56.2% speed of light, to send a probe is ok! (and this is my new record then!)

Edited August 15, 2019 by pmborg

[pmborg]

Project: InterStellar-Prob: Have a project to send a probe with payload 1850kg to AlfaCentauri in 18 (3.5+12+2.5) years only!

 

-or-

Project: InterStellar-Humans: Have a project to send a Craft with Humans in a payload 600,000kg to AlfaCentauri in 23.5 (3.5+17.5+2.5) years only!

 

 

 

Preliminary Conclusions of the InterStellar SpaceShip Study on Kerbal Space Program with ksp-interstellar mod:

 

 

 

It's possible to go on a planet of Alfa Centauri (distance: 41,386,231,576,325,600m) in 18 years of InterStellar Ship travel time:

 

·         Max cruise speed: 84,300 km/s

·         Max cruise in speed of light: (28.1% speed of light)

·         Total InterStellar Ship delta-V 168,600 km/s (56.2% speed of light)

 

 

These 19 years will have a dilatation of time of 1.042:

 

·         On Earth this 18 years will be 18.798 + 4.367 (light travel time).

On Earth we will acknowledge the landing in 23.165 years:

Edited August 16, 2019 by pmborg

[FreeThinker]

2 hours ago, pmborg said:

Project: InterStellar-Prob: Have a project to send a probe with payload 1850kg to AlfaCentauri in 19 (3.5+12+3.5) years only!

 

-or-

 

Project: InterStellar-Humans: Have a project to send a Craft with Humans in a payload 600,000kg to AlfaCentauri in 24.5 (3.5+17.5+3.5) years only!

 

Make sure you made some offering to the Kraken gods, or they might visit you .

No seriously, have you taken into account acceleration  and deceleration? Understand that deceleration can be tricky, start too early and the trip will take a lot longer and start too late and will do a system flyby resulting in a lot more time after you managed to turn around. So you going to need to calculate the exact distance you need to decelerate.

Notice the most dangeouse time will be after you final stage. Float point issues will cause the second vessel to be at multiple locations at the same time. The safest place is to be in time warp, where the Kraken can not hurt you!

Edited August 16, 2019 by FreeThinker

[pmborg]

TOTAL Distance: 41,386,231,576,325,600.00

• 3.5 years with continuous acceleration, travel distance:  4,652,348,400,000,000.00
• 12.5 years travel cruise speed, travel distance:  33,410,777,176,325,600.00
• and another 2.5 years with continuous de-acceleration, travel distance:  3,323,106,000,000,000.00

Yes indeed the trick part of the tests that I have done, is to break and enter in the Star SOI, once there I target the initial speed to be around 100,000m/s to enter/travel inside the Star System, until reach the target planet neighborhood orbit, please remind that the star will do a permanent acceleration to the ship, should keep between  200,000m/s and 300,000m/s delta-V for that.

Once near the planet,  to do the final burn to be in the Star orbit "near" of the Target planet.

Once there just a matter of doing the final planet rendezvous.

 

But yes in my generic calculations didn't discount these 300,000m/s to make sure that we will land on the planet.

Maybe the final version will have just a separated tank for that reserve

Edited August 16, 2019 by pmborg

[pmborg]

Yes, indeed I noticed that I forgot to count with a higher TWR at the deceleration, will be just 2.5 years to do the deceleration, total 18.5 years then!

Not counting time to refuel and time to final rendezvous

Edited August 16, 2019 by pmborg

[FreeThinker]

1 hour ago, pmborg said:

Yes, indeed I noticed that I forgot to count with a higher TWR at the deceleration, will be just 2.5 years to do the deceleration, total 18.5 years then!

Not counting time to refuel and time to final rendezvous

I guess the match is very similarto a suicide burn, with a very low gravity, so I guess you can use the suicide match to determine when to decelerate

Perhaps you can use this calculator: https://www.desmos.com/calculator/ms0zpkjkvp

Quote

Maths incoming.

We're going to assume constant acceleration. In reality it wouldn't be quite constant, since the mass of your ship is decreasing, making your engines accelerate you more, and you're getting closer to the planet, making gravity accelerate you more, but we're going to assume that these are both minor enough to ignore.

First we need to know the acceleration of the spacecraft. I'm going to use up as the positive direction, so the acceleration of the spacecraft is going to be

a = aEngine-g  

where g is the acceleration due to gravity where you are, and aEngine is the thrust of the engine you're using divided by the thrust. Hopfully you get a positive number...if not, you have problems.

Next we need to know how long it will take to stop. We get this from the equation

v = v_0 + at  

Solving for t:

t = (v-v_0)/a  

Since we're going down, v_0 is a negative number, and since we want to stop, v is 0. So basically, it works out to (initial speed)/(net acceleration) is the time that you need to stop.

Lastly we want to know how far we will go in that time. Under constant acceleration

dist = v_avg*t  

and since we're coming to a rest, v_avg is just half of the initial velocity.

Combining those, we get

dist = (v_0/2)*(-v_0/a) = -(v_0)^(2)/2a.

Plug in how fast you're going, and the net acceleration of your craft, and you get how far you will go before you stop (the negative sign is there just because you're going down). Now the tricky thing is that as you go down, your initial velocity also increases. When I wrote a kOS script to do this I just had it rapidly checking using the actual current velocity, but if you want to do the calculation once and be done it becomes much harder if you need to account for the changing initial velocity based on altitude. Depending on how fast you're going, though, your velocity might not change enough in the relevant range to matter.

see also : https://www.reddit.com/r/KerbalAcademy/comments/4c42rz/maths_help_calculating_when_to_suicide_burn/

 

Edit: I found a spreadsheet which might be usefull:

https://www.dropbox.com/s/0lq80ruzs8vt8az/KSP Full Throttle Burn v0 (Autosaved).xlsm

Edited August 16, 2019 by FreeThinker

[pmborg]

1 minute ago, FreeThinker said:

I guess the match is very similarto a suicide burn, with a very low gravity, so I guess you can use that to determine when to decelerate

We can use "suicide burn" when we are inside the SOI of the target, which is not the case.

I am not counting with SOI influence and in this case they should be big, because the Ship will be inside 3 different SOIs:

• Escape "Sun" SOI, will decrease the initial acceleration.
• Intercept "Proxima Centauri A&B" SOI, will decrease the final deceleration.
• Intercept "Proxima Centauri" SOI , will decrease the final deceleration.

 

[FreeThinker]

5 minutes ago, pmborg said:

We can use "suicide burn" when we are inside the SOI of the target, which is not the case.

I am not counting with SOI influence and in this case they should be big, because the Ship will be inside 3 different SOIs:

• Escape "Sun" SOI, will decrease the initial acceleration.
• Intercept "Proxima Centauri A&B" SOI, will decrease the final deceleration.
• Intercept "Proxima Centauri" SOI , will decrease the final deceleration.

 

SOI and gravity can be pretty much ignored when working on the interstellar scale, the only thing that counts are distance to target, engine isp, starting dry mass and wet mass. I would say start your burn 1 day in advance and you are set for succes

Edited August 16, 2019 by FreeThinker

[FreeThinker]

21 hours ago, pmborg said:

• As I suspected, already confirmed don't work, another stage reduce the delta-V from 124.7M to 119M:
•  
• 

Are you sure staging is correct here? what about stage 3?

[pmborg]

Just now, FreeThinker said:

Are you sure staging is correct here? what about stage 3?

please check my reply after this one about it.  ( Posted 17 hours ago )

I have now another payload instead 600tones this one have 128tones, but with no live Support, they need to be in Cryogenic Freeze all Journey

[pmborg]

 

456tones with Life Support, allow them be awake all Journey.

[FreeThinker]

2 hours ago, pmborg said:

 

456tones with Life Support, allow them be awake all Journey.

I would recommend a mix of active and frozen kerbal crew. I suggest 3 /4 Senior Kerbals (the golden ones) to stay awake and make big decisions and the rest will be  frozen as backups

From a genetic point of view you need at least a population of 50 or so to prevent inbreeding, 25 males and 25 famales

see also: https://www.britannica.com/science/minimum-viable-population#ref1215147

Or 3 x 7 = 21 females (one foe every day of the week )

see also https://worldbuilding.stackexchange.com/questions/3/what-is-the-minimum-human-population-necessary-for-a-sustainable-colony

Edited August 16, 2019 by FreeThinker

[pmborg]

Ok, thanks this are really Good inputs i will take that into account.

Btw: The mini payload version is already on 171M deltav

 

[pmborg]

• Might not look like the images of a InterStelarShip science fiction movies, but this work in the simulator...
• Can keep a crew of 6 people awake all Journey in a total of 50 colonizers with (Cryonetic Freezing), in a max of pax 56 for 60 seats.
• Delta-V 172M for a payload 2tones
• Delta-V 170M for this one:

Edited August 17, 2019 by pmborg

[The-Doctor]

As you know this challenge has long been an interest of mines but more in depth, with colonization, however I've not had much of the things I believe are needed to do this as various mods are needed to come close, such as kerbals can't give birth, outdates spaceplane parts, that sorta stuff, so I'm gonna start experimenting with modding and hopefully fill in the gaps that's needed to make interstellar colonization possible. It's easy to make a giant laser powered sail with a kerbal in deep freeze to get to another star lol, making it realistic is what I think is good

[pmborg]

19 hours ago, The-Doctor said:

As you know this challenge has long been an interest of mines but more in depth, with colonization, however I've not had much of the things I believe are needed to do this as various mods are needed to come close, such as kerbals can't give birth, outdates spaceplane parts, that sorta stuff, so I'm gonna start experimenting with modding and hopefully fill in the gaps that's needed to make interstellar colonization possible. It's easy to make a giant laser powered sail with a kerbal in deep freeze to get to another star lol, making it realistic is what I think is good

• I will use the "Kolonization" parts on "Von Broun" planet (target), I have a "Container Kit" with a "small factory"
• Inside that "Container Kit" is a big and mobile Factory, and after that I will create a House Colony to farm materials from drilling
• and then with those materials I plan to do the Colonization using the "Kolonization"

@FreeThinker,

If is possible, I would like to have your help/suggestions to reduce the weight on these parts in tones:

Any Idea? Specially the red ones.

Please note that the BigSphereTanks are empty

 

Edited August 17, 2019 by pmborg