The KSP Interstellar Proxima Centauri Challenge

[juanml82]

Ok, I think I'll try to bite. I'm using RSS + SMURFF + Far Future Technologies + No life support + EPL to expand the base

The Far Future Technologies Z-Pinch fusion drive can get me ships with over 300,000 m/s dV with a large payload. If I'm reading things right, that should mean I should be able to put the ships at 0.3-0.5c and have enough to circularize at Proxima and then maneuver to Proxima B, right?

How do I go about burning towards Proxima Centauri? Do I get into solar orbit (so the navball doesn't become a mess when leaving Earth' SOI), select Proxima as a target, point the ship towards the target using the navball and fire the engines?

As I see it, the mission profile is as follows:

The travel times should be fast enough so the fission reactors powering the ships (and keeping the fusion fuel tanks cooled) don't run out. Rtgs wouldn't last the journey and solar panels will only be useful once close to Proxima. And without power, I loose the fuel and can't slow down at the destination.

The target planet has no moon to serve as a gas station, a 54km high atmosphere which only gets thick below 5-10km, so it's hard to use to slow down, and it takes about 8,000-9,000 dv to land or achieve orbit.

Nertea's FFT engines tend to be useless in an atmosphere, except for the nuclear salt water engine. But considering it's a colonization and not a "let's irradiate the whole place" mission, a ground rule of not using NSW engines inside B's atmosphere must be established. For the same reason, ships can't stage away nuclear thermal engines while in the atmosphere or in suborbital flight.

So in other words, landers have to use conventional engines or, if they use nuclear thermal, they must be SSTO (or more precisely, Single Stage to the Surface). LH2 can't be kept in the tanks for such a long trip without boil off, and even methalox may strain the electric power budget for the trip. So it's either LFO ships, or they use LH2, but will carry ore and convert it into LH2 once in the orbit of Proxima B. The ore tanks can be used as pretended shields against high velocity particles during the journey (yes, yes, they aren't modeled in KSP, but let's pretend it's important)

A scansat satellite should also be brought, in order to find a good base site and also to explore Proxima C.

So, the tentative plan is as follows:

A space station with a large centrifugal habitat carries the kerbals. This ship doesn't land, and will remain in orbit around B.

One single stage to surface lander with a nuclear thermal aerospike. The landing will be assisted with parachutes. Since it uses LH2, it will travel with the tanks dry and an ore tank attached to the top in order to produce the fuel in orbit (oh, yes, a moon would have been so convenient). In can also work as an SSTO for the colony, but without a moon, it can't refuel in orbit, so once it reaches orbit, it can't go down again.

Two barely mobile bases made with Planetary Base Systems, one for ore mining (and fuel production) and nuclear fuel recycling, the other for EPL and OSE Workshop production. They will be delivered with spaceplanes, which can stay in the low atmosphere long enough to slow down - they'll use inflatable heat shields to provide additional drag. Their hopefully controlled litobrake will be parachute assisted. If the spaceplanes survive, they'll serve to explore the place. Since I won't be able to reliably aim at the landing site, the bases will drive there using Bon Voyage. The bases mass is in the 16-18 tons range.

A scansat satellite with a vasimir engine will be delivered with some of these ships.

 

EDIT: Huh... right, no. The speed of light is about 300,000 km/s. 300,000 m/s is one thousands of that

Edited January 14, 2022 by juanml82

[Zapataz]

Hello from Proksima!

After borrowing some ideas from GenerallyCompetent I improved my previous travel time achieving Kerbin-Proksima in a bit less than 10 years with 9 years and 350 days. I hope you will forgive me to be too lazy to bring the space ship into Kerbin orbit. This time it's not a trivial task as this one is 2738t.

• Travel time 9 years 350 days
• Max speed: about 260,000,000 m/s that's about 0.86c
• Best acceleration: 1.31m/s
• Weight: 2,738.00t
• Height: 145m
• Cost: 27,367,040
• Parts: 68
• Team: 4 people with nice rotating flats for a very long trip
• Main engine: 4xMach effect drive powered by a quantum singularity reactor
• Magnetic scoop for slowing down the ship and retrieving hydrogen while traveling.
• Lander: powered by a positron reactor and the engine is a Krusader thermal nozzle

During their long journey, the crew fought nasty Krakens and bugs. A some point I had to use version 11 instead of 12. When entering the SOI of Proksima KSP just crashed. I'm not sure what is the cause of the issue. It worked with an old version. In addition the top speed during time warp was more "stable" allowing to achieve a nice acceleration: at high time warp acceleration is not constant and fluctuate rapidly BTW I was not able to achieve more than about 2g for deceleration using the magnetic scoop due to the game complaining that acceleration is not possible in time warp.

I'm guessing that with a better navigation it's possible to improve the travel time. But I believe the acceleration is close to the best possible with a Mach effect drive. Having larger Mac effect engine will help to take a heavier payload, this should allow the Kerbality to colonize all the stars around

Some pictures here: https://postimg.cc/gallery/W1KVjxT

Edited March 11, 2023 by Zapataz

[FreeThinker]

Although not an official participant, It is a relevant video

 

Edited March 21, 2023 by FreeThinker

[Zapataz]

Eventually I managed to assemble my interstellar vessel in orbit of Kerbin. For that I used Kerbal Space Transport System mod. I added some screenshots in the gallery https://postimg.cc/gallery/W1KVjxT I lost the track of the exact cost but should be:

• Workshop: 342.000
• Shuttle for transporting crew: 158.000
• Cargo with parts: 4 flights of about 7.500.000 each
• Total about 28.500.000

Thanks to the way KSTS calculate the construction time, packing a bunch of Kerbals in the workshop leads to only 5 days of construction time. Thus total construction time and flight is still less than 10 years with 9 years and 355 days.