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How will you get to one of the planets?


Candre

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My question is how do I know if my parachutes will be able to slow me down enough in the atmosphere? What are the calculations for this and what do I need to know in order to make sure that I know that my parachutes will slow down my craft enough upon descent?

My solution is that I put on as many parachutes as I think I will need. Then I double that number. Then I put a few more on for good measure. Then I sit there and watch my craft descend at a painfully slow 2 m/s.

Or more boosters. That always works too.

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Also what about the window of opportunity to actually launch a rocket to Murs?

i know that when NASA sends their rovers to mars they can only do this once every few years because doing it at any other moment would increase the required fuel costs dramatically.

Would it be possible to pick a launch date and have the universe warp forward until the planets are properly aligned??

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I would think that if the new planet has say 20% of the atmosphere, you can probably expect it to work with 20% of the effectiveness. The parachutes we have are calibrated to land a command pod, and perhaps a little bit of extra weight (like an ASAS module, however heavy that is), on Kerbin. So even if your just landing a command pod on this new planet (so nothing to get you home), a chute isn't going to cut it. At least not the ones we have now. Your going to need a retro burning engine, or wings and probably an engine to keep your speed up.

I align the Mun when I launch because of my prefered method of getting there, and it would be very expensive if the Mun was at any other point. For Minimus I haven't found it to be a problem.

So it could be part of the planning, but part of the challenge would be building a rocket with the interplanetary stage(s) being able to handle a variety of positions. Each stage of my rockets is designed for a specific part of the flight, with what is intended to be a little bit of extra built in, in case a stage has problems or I mess up, so it's not uncommon to be jetessoning a little bit of extra fuel once that stage is no longer able to be useful (normally once a given configuration is too heavy, and I need something more maneuverable). However, launching to a planet on the other side of the system would certainly not be optimal. You want to launch probably when the new planet will be located the shortest possible distance from Minimus, when you arrive there.

Edited by Randox
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I did some testing and designed this rocket for interplanetary travel (some parachutes and landing-legs aren't added yet). More than enough fuel to reach another planet and perhaps even return if the destination planet has low gravity and thin atmosphere (or none ... !)

15gw1w8.jpg

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I've also done some testing and have created a craft capable of getting a ship with four full fuel tanks and a small one tank lander into a slightly larger than Kerbin orbit. And during this test I got the craft into a circular orbit of what a Mars analog in the Kerbol system would be at (about 22,200,000,000 meters, based on the system being a 1/10th scale) and then I burned back to try and return to Kerbin...

But failed quite horribly because I forgot I would accelerate while I was going down to the 13,500,000km orbit. with a bit better of planning I would've hit home.

I do plan on making changes to this craft thought, like possibly adding another tank to the travel stage (as to most certainly not run out of fuel escaping the new system [it would probably also be best to park in a high orbit, as to minimize fuel for the escape{I think}]) and an empty capsule on top of that to actually be able to return to Kerbin seeing as how the lander will NOT have the fuel necessary to do so. So the lander with have to meet-up and EVA the crew over to the travel crew.

Hmmm... maybe I should have the lander have the empty pod, as to not run into any staging mishaps. Plus it feels more like the Moon landings and such.

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At the moment, my plan is to set up an orbital construction dock or similar around Minmus - its low gravity and position near the edge of the planet's SOI mean that it should be easy enough to launch from, and I shouldn't have to pack that much power to fight against gravity on the way up. Minmus landers are already easy enough.

Step 2 would probably be a high-efficiency, high-fuel interplanetary module. It will probably carry a few boosters to get it going from Minmus, but once it is off it only really needs one engine to change the orbit to match that of the planet I am visiting. I'll use the fuel tanks with the most capacity per weight and attach them so that they can be decoupled once empty to increase performance. I'll have to do some maths using the weight of decouplers and fuel lines to see how often to decouple in order to save weight, and thus how to arrange the tanks.

Step 3 would be a large lander for the last planned step, carried by the previous stage. On approach to the planet I will perform a quick scan, but only of the orbit that I am in when I approach - the best landing site in that orbit will be where I get off. The descent itself will probably be a retro-thrust assisted by parachutes to soften the landing. At this point I will probably pull a quick EVA, grab screenshots, et cetera.

Step 4 is an escape from the planet and a return home. I don't actually expect to have enough fuel left for this - in which case, I will try instead to put my brave explorer Kerbal either into orbit or onto one of the moons of the planet I visited, if it has any. This should make it easier to rescue them than simply leaving them on the surface. In addition, the moons of the planet can be cause for more sweet screenshots, or if I get into orbit I can scan for further landing sites for future missions.

Future missions:

- Get a second construction station into orbit around the target planet, or one of its moons. Being able to reconfigure the rocket at each step means I may be able to get several smaller landers out of each interplanetary journey, instead of being forced to either use all of its cargo at one time or underuse its carrying capacity.

- Put probes into orbit and fully map the surface.

- Place a base onto the planet itself. Man, that would be so fun. And dangerous. I would probably break it before it even got near to the planet.

- Fill up the construction station with a metric freakton of fuel. In future, it can be used as a refuelling depot for interplanetary flights going further away from Kearth.

What do you think?

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I think you'd be surprised how little fuel you would need to go to another planet compared to the moons.

Well, You certainly would need a bit more, but not as much as you'd think. On earth, going to the moon compared to mars is only a small difference in delta velocity, if I recall correctly.

42,000 mph to get to the moon.

48,000 mph to get to mars.

Of course, the hard part is timing everything out correctly given the current systems in KSP.

My source...

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What do you think?

that sounds exactly like the plan I'm going to do to get my kerbals on the red planets but mildly simpler. Instead, my mothership would take more than just a lander. It will take a planetary habitable pod, a surface escape space plane, 2 mannable rovers (one each for the planet and moon), a moon lander, an emergency space vehicle (just in case the surface escape space plane and moon lander doesn't have enough fuel to return to the mothership; they should have enough fuel to get into orbit though), 2 unmanned rovers, 3 satellites, 4 probes (the probes help me get a feel of landing on a unfamiliar planet) and 40 kerbal mass units of "dead weight" as a stand in for food and supplies. In all, the vehicles and supplies the mothership will carry would be around 300 kerbal mass units. I will get the vehicles to the red planet via an orbital construction spacedock on the mothership. I will also add the 300 kerbal mass units of dead weight on the mothership to simulate it bringing the vehicles to the planet. I am confident that the mothership would be able to get its load to the red planet. I'm am also reasonably confident it can go back home. I mean, come on, it has 99,200 fuel units on it. 9 kerbals would take this extended mission. 3 on the planet. 2 on the moon, 3 in the mothership acting as command central and controlling the unmanned craft. And 1 lone kerbal in the emergency space vehicle acting as command central for the moon kerbals.

So what do you think of my mission?

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I'm probably going to first send a probe to collect data about the target planet (diameter, gravitational parameter, atmospheric data). Following that, I will be able to design a manned mission that will go there and back.

I already have my spreadsheet ready for calculating all the necessary information needed to get me from one planet to another.

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Does anyone know the calculation/formula which helps you time when to do and where to do your burn to get to the other planet? I won't be able to do it Kerbal Style anymore I guess considering the planet will be about ten times as far away as minmus.

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Just did a prototype for a planetary rocket with (hopefully) return capability. It's no less than 6 stages (not including SRBs). It's all stock except for a MechJeb. Now I just need some planets!

7738943254_b55e9e8888_c.jpg

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7738940828_98e82a06f6_c.jpg
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Does anyone know the calculation/formula which helps you time when to do and where to do your burn to get to the other planet? I won't be able to do it Kerbal Style anymore I guess considering the planet will be about ten times as far away as minmus.

I'd expect a planet to be at least a hundred times further from Kerbin than Minmus at closest approach, and would wager on it being significantly further..

At any rate. here: https://docs.google.com/document/d/1IX6ykVb0xifBrB4BRFDpqPO6kjYiLvOcEo3zwmZL0sQ/edit

Note that the angle produced will only really work for circular and near-circular orbits of the destination objects, and even for those, you're still going to have to do some maneuvering to find that SOI on final approach.

I would recommend that any potential planetary explorers do the "Leave the Kerbin SOI, orbit Kerbol at least once, then return to Kerbin" mission to get a feel for what finding a planetary SOI at interplanetary distances will be like, using the current instrumentation.

Edited by maltesh
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Step1: Make gigantic rocket capable of making Kerbol Escape

Step2: Launch in vague direction of new planet

Step3: Wait until my cat gets off the keyboard

Step4: Profit.

I like the way you think, though I have found my missions are more successful if I let my dog lay on my keyboard instead of a cat.

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See here.

As stated in the posted linked above I'm going to use the new Fuel Transfer plugin and launch tanker/probes as required. Not a stock approach granted, I prefer the variety over being locked in to just a few parts. :)

The 200 ton tanker shown there is a little big to send on an interplanetary jaunt but I'm sure I can make something more suitable.

If all goes according to plan, two launches should let my SSTO land on any of the planets, before refuelling for the trip home. One launch for the tanker and a second for the manned SSTO. Nice easy mission plan (hopefully). I've noticed that the Fuel Transfer plugin still has the odd bug. So there will be quite a risk involved as my intrepid Kerbonauts may discover the refuelling gear may suddenly go FUBAR. I look forward to interplanetary rescues!

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Fairly simple - get into an orbit SLIGHTLY lower than the planet I'm aiming for (well within its SOI, but hopefully not going to smack into the surface), time warp, wait until I reach my periapsis, burn retrograde until I'm in orbit, and then do whatever I was going to do. I know that all of my spacecraft will be equipped for landing on just about anything. Returning, well, that'll be extremely not fun.

Of course, unless I rebuild the old Xenatan 7, and glue a few more of its fuel tanks on the side, I'll need to launch from the damn runway to not have my rocket be inside the tower...

Edited by leopardenthusiast
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Fairly simple - get into an orbit SLIGHTLY lower than the planet I'm aiming for (well within its SOI, but hopefully not going to smack into the surface), time warp, wait until I reach my periapsis, burn retrograde until I'm in orbit, and then do whatever I was going to do. I know that all of my spacecraft will be equipped for landing on just about anything. Returning, well, that'll be extremely not fun.

Of course, unless I rebuild the old Xenatan 7, and glue a few more of its fuel tanks on the side, I'll need to launch from the damn runway to not have my rocket be inside the tower...

I suspect you'd be shocked by how long riding the inside/outside track can take given interplanetary distances and the typical size of planetary SOIs, even given 100k time accelleration. And the farther out the planet, the flatter the rotation curve, and longer the periods, so the slower this will go.

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I suspect you'd be shocked by how long riding the inside/outside track can take given interplanetary distances and the typical size of planetary SOIs, even given 100k time accelleration. And the farther out the planet, the flatter the rotation curve, and longer the periods, so the slower this will go.

Don't worry, I have unlimited supplies of free time. If free time was worth any amount of money, I would be an infinityaire or something. And kerbals live forever if they're not killed in a rocket crash.

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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.

Edited by maltesh
Added Hohmann transfer time.
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Squad will probably add a new computer guidance system like mechjeb to get you there

And you wont even need as much fuel as you guys are making it out to be

To get to a planet like Mars you would only need about 1 tank of fuel at max depending on the weight of your craft

you only need to get on a trajectory to the planet

and only you get close enough you could burn to get your orbit smaller

I hope we will be able to send unmanned rovers like the ones that land on Mars

Edited by lolmama
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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.

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