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How will you get to one of the planets?


Candre
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That, or we can wait for kosmo-not to get a guide up. That, or I will get a guide up. Actually, I already posted a rendezvous guide that is perfect for interplanetary rendezvous. Some people had a hard time understanding it though so the thread kinda died some months ago. If you want me to post the url, just say so. I'll probably rewrite it to make it easier to understand a week before .17 is released. That, or kosmo-not will get one up before me.

Could you post the URL?

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That, or we can wait for kosmo-not to get a guide up. That, or I will get a guide up. Actually, I already posted a rendezvous guide that is perfect for interplanetary rendezvous. Some people had a hard time understanding it though so the thread kinda died some months ago. If you want me to post the url, just say so. I'll probably rewrite it to make it easier to understand a week before .17 is released. That, or kosmo-not will get one up before me.

I've been kinda lazy lately. I guess I can try to get the guide finished today.

I'm interested in seeing your work, too. So don't let me hold you back from publishing your own guide.

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Prior to .16 I was able to make legit vanilla ships with enough fuel / delta v to sundive nearly vertically into kerbol. So I'm not too worried about that aspect. I'm more concerned about being able to make return trips. / hitting the SOI's / timing the launch window.

It'll probably be like how I ended up getting to the Mun when I first started playing. Fudge it for a while, have a lot of near misses / slingshot escapes. Then eventually get motivated to break out the orbital mechanics and make more educated 'fudges'.

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I think two-ship missions will be a must-have until docking is added. Until then, it would not be feasible to launch a whole ship there, have it land, and return. The amount of lag on takeoff would bring most computers to their knees.

Until docking, my missions would go:

Build 2 ships capable of flying to orbit remote planet, each with a payload.

Ship 1 payload: Lander, and orbit stage.

Ship 2 payload: Passenger module, return-to-kerbin stage, parachute.

Ship 1 lands, takes off, rendezvouses with ship 2, crew transfer, returns to kerbin. Celebrate success.

After docking is added, it would be far simpler, in that it would go:

Assemble, by means of multiple supply flights, big-ass station in kerbin orbit, with engines, tons of fuel, and a lander return stage.

Fly station into kerbol orbit, rendezvous with target planet and orbit.

Lander/return stage goes to surface, does science, returns to 'mothership-station'.

Jettison lander stage, keeping the module that the lander crew are in. (could be achieved by a lander that has a pod, with a docking port on top, and a decoupler below, and the lander below that. Once it's back at the station, the lander can be ditched, keeping the pod and eliminating the need for an extra crew module)

Return to kerbin, park in low orbit. Adjust ship to sub-orbital trajectory, detach all crewed modules (probably just one, maybe two) and re-enter atmosphere.

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The problem definitely won't be the fuel to get there, but the fuel to get back will be problematic. It really is a shame that we won't have docking. It doesn't make much sense to plan interplanetary expeditions without a way to dock a separate lander module or to refuel ships. Imagine a rocket big enough to take you from Kerbin to that planet. Then imagine the rocket capable of putting that fully fueled interplanetary rocket in one piece on another planet (including the semi-powered descent because parachutes will probably not be very efficient).

My plan for 0.17 is to ignore return trips for the moment (because without docking, it is just silly) and only send one-way unmanned probes and rovers, probably with Munolith detectors and cameras. This will allow me to perfect my navigational skills and figure out the best entry and landing techniques so that I can send a lander and a return ship when docking is released.

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You wanted the url so here's the url. However let me warn you of a mistake most people make when they attempt this method: Many people assume altitude is the same thing as orbital radius. However its not. in order for you to derive orbital radius from altitude, you must add the planets/star's radius to the altitude to get orbital radius. After you convert it to orbital radius, you then can multiply the number by .63 or 1.59. (you'll understand that multiplying part once you read the guide) Remember that once your done multiplying, you need to convert it back to altitude so subtract the product by the planet/star's radius to finally get your starting altitude. Kerbin's radius is 600,000m by the way. Last time I checked, kerbol doesn't have any diameter but check to make sure.

And finally the link (don't post anything; remember its a dead thread) :http://kerbalspaceprogram.com/forum/showthread.php/6642-How-to-rendezvous-with-other-orbiting-spacecraft?highlight=rendezvous+orbiting+satellite

I will recreate this thread before .17 comes out and improve on it to make it easier to understand. You can practice the method inside the Kerbin system with the moons (minmus is great for low-to-high method) or better yet your own target satellites (there better because gravity doesn't get in the way) You can also try and go out in kerbol orbit and try to rendezvous with kerbin if you dare. It is possible, I've done it before.

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Two words - ion engines. I'd probably use 4 or five solar powered ion engines - that should get us into any orbit. Then I might use the controllable debris mod to send a lander or descent vehicle down to the surface. I might land the entire vehicle on a low-gravity airless moon.

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I just thought of a great idea. I think I can make a small interplanetary vehicle that's powered only by RCS. Never underestimate the power of RCS guys; I've got really small, single-staged, and light vehicles to land on the moons only using RCS starting from the surface of kerbin. I'm going to design one now.

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If someone makes an ISRU mod, then I'll try a Mars Direct style mission. After emptying the return vehicle's tanks on the pad, I'll send it to the target planet to start producing fuel. Then on the next launch window I'll send a lander holding the Kerbals and a rover. Once on the surface, I'll explore using the rover, making my way over to the return vehicle so I can head back to Kerbin.

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Fair enough.

Still, I'd balk at spending nearly two hours at 100k time running the nearly 20 years that would be the average catch-up time for an inside-track attempt on a planet 20million km from Kerbol, and assuming an SOI the same size as Kerbin, assuming you didn't go for a specifically-timed launch window.

Said launch windows, for a planet 20 million km out, would occur about every 241 days. Hohmann transfer time: 73 days.

That long? Also not hard: Just go the other way. If I know what I'm talking about - and I probably don't - it's much easier to catch a planet when it's moving toward you.

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That long? Also not hard: Just go the other way. If I know what I'm talking about - and I probably don't - it's much easier to catch a planet when it's moving toward you.

If you go the other way, and circularize yes, you'll hit the hypothetical Far Planet in up to half a period of the planet at 20million km after reaching that altitude..

The problem is going the other way.

Let's assume you do the (relatively) sane thing, and Hohmann transfer out from Kerbin's orbit to the 20 millon Km planet's orbit, then reverse course and circularize. and attempt to come into it head-on. (Reversing course at Kerbin's orbit is going to significantly more fuel-hungry) When you arrive out threre, you'll be moving at 6.9km/s.

To reverse course, you'll have to kill all that velocity, then pour on another 7.6 km/s to circularize. So there's an extra expenditure of 14.5 km/s delta-V.

Going the normal way, You'd be moving at 6.9 km/s at apoapsis, and only have to boost up another 1.5 km/s to circularize. And if you waited for a launch window, the Far planet will be nearby, and you might not even have to circularize.

So, by reversing course at the Far planet's orbit, you spend an extra 13 km/s of delta-V over if you'd gone the right way. That is a lot of extra fuel you had to bring along.

Also, if you've decided to come into the planet head-on, you'll be moving at more than 15 km/s relative to the planet when you enter the planet's SOI. Kerbin's atmosphere could probably eat that. A hypothetical Far Planet's atmosphere may not be so accommodating.

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