Stuck in Orbit Around the Sun With Tourists - Help!

[Qcumber]

In early career mode, I selected a contract where I have to take two tourists on an orbit around Kerbin. Let's just say I'm not very experienced at getting to orbit and somehow I managed to escape Kerbin and went into orbit around the sun (ctrl-z didn't do what I thought it would do...). I did get a lot of science from it, but I need to get the science, and the three stranded Kerbals back to home.

What should I do? I have no fuel left. Should I just use time acceleration and hope my vessel will intercept with Kerbin again? Or should I somehow plan a rescue mission (and how should I do it?)

Here's the screenshot:

 http://imgur.com/a/qoVjc (I can't seem to upload it directly onto here)

Thanks!

[Fixed by Snark to embed screenshot]

Edited January 8, 2017 by Snark
add in-line image

[Snark]

Fixed the screenshot for ya.    (You were linking to the Imgur page, not the image itself.  To embed a screenshot, just right-click on the image in imgur and choose "copy image location", and paste that (i.e. the url ends with ".png").  Then the forum will automagically convert it to an inline image for you.)

 

10 minutes ago, Qcumber said:

Should I just use time acceleration and hope my vessel will intercept with Kerbin again?

You could try... but you'd likely be waiting a long time to get an intercept.  Likely decades or even centuries, Kerbin-time.  Planets (and their SoIs) are very tiny targets in the solar system, it's hard to hit them by accident.

11 minutes ago, Qcumber said:

Or should I somehow plan a rescue mission (and how should I do it?)

Basically, this is your only option, unless you want to just blow off the contract and take the cash+reputation hit that that would entail.

A rescue mission is straightforward, but requires some KSP skills that you may not have developed yet, if you're new to the game.  You may want to leave a rescue mission until a bit later, when you've had more practice (unless you're rarin' to go for the challenge right now!) 

There are basically two challenges you'll need to conquer in order to have a rescue mission:

1. Be able to design a ship with enough dV.
2. Have the navigation skills to set up an interplanetary intercept.

Of the two, I suspect you'll find #2 to be more of a challenge than #1.

Reason:  You probably don't need a super high dV to be able to rescue.  From the looks of your screenshot, the stranded ship's solar orbit isn't that much different from Kerbin's, which tells me that it didn't leave Kerbin's SoI with a really big Kerbin-relative velocity.  That's good news, because it means you don't need super-high dV to rendezvous with it, either.

Basically, once you get your rescue ship into LKO, you'll need ~1000ish m/s of dV to be able to escape Kerbin's SoI, plus some amount to give it the desired intercept orbit, plus some amount to match velocities when you encounter the target, plus some amount to then put it on an intercept course back to Kerbin.  So, your rescue ship is going to need the following:

• To be on the safe side, let's say ~2000 m/s of dV remaining, after getting to LKO.
• A heat shield, to survive the return to Kerbin (if you're bringing the rescue ship back).
• Some way of docking to the stranded ship (since you can't EVA the tourists).  If the stranded ship happens to have a docking port on it, you can dock that way.  If it doesn't, then your only hope is for the rescue ship to mount the Klaw, so that it can grab the stranded ship.

You may be scratching your head about my above comment, "if you're bringing the rescue ship back".  Well, of course I'll bring it back, that's the point, you're probably thinking. 

Well, there are basically two options for handling the rescue.  Both options require the ability to dock.

• One option is to send a rescue ship that has some empty seats for the stranded kerbals, and enough fuel to come home, and a heat shield and parachutes and such.  You dock to the stranded ship, transfer the kerbals across, undock, and bring home the rescue ship.
• But there's also another option:  A refueling rescue ship.  This can be a completely unmanned ship with no crew capacity at all, but extra fuel tankage.  It docks to the rescue ship, then it transfers fuel to the stranded ship, then it undocks.  Now you can bring the stranded ship home using its own engines, and you just abandon the rescue ship in solar orbit.

 

...Anyway, that's it for the engineering challenge of building the ship.  Then there's the matter of getting a rendezvous with the stranded vessel.  That's an exercise in interplanetary navigation:  first, you need to set up an intercept so you can meet the target; then, after you've done the rescue, you'll need to set up another intercept to get it back to Kerbin.

That's perfectly doable, but if you've never done it before, it can be a bit of a challenge.  Do you have experience with rendezvous, docking, etc.?  If not, I'd suggest doing some practice in Kerbin orbit to get the hang of it, before you try something ambitious like a solar-orbit mission.  For example:  put a couple of satellites in different orbits around Kerbin, then try sending a ship to dock with satellite A, then leave that to go dock with satellite B, then back to A again, and so forth.

You may find it tricky at first, but it gets a lot better with practice.  There are some good tutorials out there for learning orbital rendezvous techniques, plus of course you can always ask questions about it here. 

Good luck!

[diomedea]

Best would be to revert to a previous save (look also at those files in the "Backup" subfolder with your game, may be they help). If you have none, be prepared to "cheat" the game. That ship may indeed encounter kerbin again, but could take years to have an encounter (not less than the synodic period with the orbits of the ship and kerbin around Sun) and then you have no fuel to change periapsis, you'll probably miss kerbin or hit it at astronomical speed. Planning a rescue in solar orbit is no small feat and could take a very long time too.

If you want to consider cheating, you need to "put" a bit of fuel back into your vessel, then use the "infinite fuel" cheat from the debug console (Alt-F12). To put some fuel back you need to edit your savegame, find your vessel in it (look for a VESSEL with name = <nameofyourship>) and within your vessel find a tank (you can just look for a line with "name = liquidfuel" and another with "name = Oxidizer" if both are required). Change the lines with "amount = ..." to read the same quantity as in the following lines "maxAmount = ...". Repeat for more tanks. Please know that even with infinite fuel a return trip to Kerbin will take time and is better to plan it carefully.

[bewing]

Hmmm. This is a toughie. First, unless you got really lucky with the "resonance" timing, it's going to be about a million years until that ship happens to intercept Kerbin's SOI again. I can guarantee it will happen eventually ... but that's not really saying much.

So, as you say, a rescue mission is the right answer ... but that ship is already really far from Kerbin. You can't just launch interplanetary missions at any old time you feel like it, unless you have almost infinite fuel -- otherwise, you need a window, and they mostly only come around once a year. Additionally, getting there in a reasonable time is going to require a lot of velocity, which means a lot of dV, which means a lot of fuel -- and which probably also means more tech than you currently have. But since your next launch window looks like it's about a year away, you have lots of time to prepare.

 

 

[Kryxal]

I have this sneaking suspicion that the best way to do this will be ejecting from Kerbin with an apoapsis higher than it, to get the right period to match up next orbit.  This takes place where your ship touches Kerbin orbit, of course.

[Magzimum]

If you are " not very experienced at getting to orbit " (quote from OP) then almost all the advice above is far too advanced for now. @diomedea gave some good advice though: try to go back to an older save game.

Instead of helping you how to get to that ship, I am going to give you advice how to proceed with your career game:

• Leave the tourists in solar orbit for now. Do other missions first. Advance your tech-tree. Learn.
• Get comfortable with rendezvous & docking around the Kerbin system (incl. Mun & Minmus).
• Do a few visits to the planets: Duna (and Ike) and Eve (and Gilly). Send a probe to Eve for now - landing on Eve is usually a one-way mission. Try to get to Duna and back with a crew. Contracts will probably come up for this.
• Once you are comfortable with rendezvous, docking and getting to planets, you can try to get these tourists back.

Hopefully the tourist-mission does not expire before then. But it if does, then you will take a hit in the reputation, and also in cash. It is quite likely that you will screw up many (many many many!) other things before you can attempt to get these tourists back. And at some point it may be easier to start a new career, and do it properly from the start...