Talfryn Posted July 14, 2011 Share Posted July 14, 2011 Since most people (Myself not included) seem to find regular orbits fairly easy, I was wondering if anyone had done something a bit more fun, like a Molniya orbit? I'm not sure if they are out of our realm without more advanced tools for calculating trajectory and orbit, but I'm sure somebody knows how to get into one.Feel free to talk about anything interesting you have done/noticed/want to do with orbits. Link to comment Share on other sites More sharing options...
Ntmoore19 Posted July 14, 2011 Share Posted July 14, 2011 This can be done by simply going faster than the required speed for a normal orbit, and maybe aiming a few degrees above the planet initially. I've only tried it once, and I appeared to be leaving the planet, so I aborted. : Link to comment Share on other sites More sharing options...
Sordid Posted July 14, 2011 Share Posted July 14, 2011 I appeared to be leaving the planet, so I aborted. :And by 'aborted' you mean 'told the ground crew they could have the rest of the day off and left the astronauts to die horribly in the deep blackness of space where nobody could hear them scream', yes? Link to comment Share on other sites More sharing options...
Ntmoore19 Posted July 14, 2011 Share Posted July 14, 2011 And by 'aborted' you mean 'told the ground crew they could have the rest of the day off and left the astronauts to die horribly in the deep blackness of space where nobody could hear them scream', yes?Jeb seemed to be ok with it. Link to comment Share on other sites More sharing options...
Talfryn Posted July 14, 2011 Author Share Posted July 14, 2011 xD. We callously throw away thousands of cloned Kerbals... :'(All of the times I've seen this being possible, the rocket was going too fast and would only come down in theory after a lot of time. Something going up to the 800KM range at apogee would be cool. Link to comment Share on other sites More sharing options...
Johno Posted July 14, 2011 Share Posted July 14, 2011 'Hey boys, we have a procedure for you. Open the window.' Link to comment Share on other sites More sharing options...
Ntmoore19 Posted July 14, 2011 Share Posted July 14, 2011 'Hey boys, we have a procedure for you. Open the window.' Now that's just Cruel. Link to comment Share on other sites More sharing options...
Zeroignite Posted July 14, 2011 Share Posted July 14, 2011 And by 'aborted' you mean 'told the ground crew they could have the rest of the day off and left the astronauts to die horribly in the deep blackness of space where nobody could hear them scream', yes? Congratulations, you're in my signature Link to comment Share on other sites More sharing options...
Zac_Dai Posted July 21, 2011 Share Posted July 21, 2011 Achieved this last night by accident, Apogee is 1,025,600m and Perigee is 345,780m.Left it running over night just to make sure it was stable and after 14 hours my brave Kerbals are still stuck in orbit. Only problem is I have 1/6th of a tank left and I've never done a de-orbit before, so they may be up there forever lol. Link to comment Share on other sites More sharing options...
TempestGod Posted July 21, 2011 Share Posted July 21, 2011 Wait, are you saying its easy to do regular orbits? I can only seem to get the eccentric ones. Mine seem to go from about 45km perokee to a 145km apokee. No matter what i do i cant seem to go into a more circular orbit. Right now my Kerbonauts are on a nice long trip, stuck in orbit, with no fuel left for getting back. Its on about hour 11 right now. ;P Link to comment Share on other sites More sharing options...
WernherVonKerman Posted July 21, 2011 Share Posted July 21, 2011 The Java and web based calculators here: http://kerbalspaceprogram.com/forum/index.php?topic=647.0 help a lot with these. On my current mission I started at an altitude of 124km, did a transfer out to 3000K, at apogee I slowed slightly to come back in with a perigee of 50km. I actually leveled out at around 48km and accelerated so I should exit with an excess velocity of around 460m/s and enough fuel to hopefully reverse and actually bring them home safely.. hopefully. Did all my figuring with those to calculators, will see how it turns out tomorrow. Link to comment Share on other sites More sharing options...
TempestGod Posted July 21, 2011 Share Posted July 21, 2011 I have tried using thoes calculators but with no success. I think i just need more practice. I just feel sorry for the kerman brothers though. I left them orbiting while i am at work. I will end it when i get home, i just want to see how many orbits they will do. I do have to cry for them a little bit though. :'( They are so close to the Kerth, but will never be able to return home. Link to comment Share on other sites More sharing options...
WernherVonKerman Posted July 21, 2011 Share Posted July 21, 2011 I think i just need more practice. Always adjust velocity when at either apogee or perigee. If you want to control it, level your orbit out at the top or bottom of the eccentricity by accelerating or decelerating to the circular orbit velocity. Once leveled out you can accelerate into a transfer orbit that will leave you an eccentric orbit with perigee where you started and apogee at the transfer target. Once at apogee you can level out by accelerating to the circular orbit velocity for that altitude. Lesson complete. (it is the How To section. -.-) ;D Link to comment Share on other sites More sharing options...
Calypso Posted July 21, 2011 Share Posted July 21, 2011 I remember my first orbit was very eccentric, about 230k - 1600k.Only let it orbit twice before attempting to re-enter, but that failed massively with only 1/5th a tank of fuel left Link to comment Share on other sites More sharing options...
Johno Posted July 21, 2011 Share Posted July 21, 2011 I am currently in my most circular orbit yet. And it took roughly two orbits (and goodness only knows how much propellant) to get there! Whoever said that it's easy to get a circular orbit must have had their brain replaced with digital components . . . Link to comment Share on other sites More sharing options...
P.Funk Posted July 21, 2011 Share Posted July 21, 2011 My question is what do you do to further stabilize your orbit when already at the circular velocity needed? If I'm at say 200km at my apogee above Kearth and the calc says I need to be going 2100.7 m/s to be in a circular orbit, and I am what do I do to change the fact that I'm continuing to rise and fall? Do I burn to change vertical speed? Is it actually possible to remain in a window the size of a few meters? Do we just not have the instruments to calculate this right now? Link to comment Share on other sites More sharing options...
WernherVonKerman Posted July 21, 2011 Share Posted July 21, 2011 It is extremely difficult to get an apogee-perigee within even a couple hundred meters. But the best way to level it out is just boost a tiny bit at every apogee till you get the speed fine tuned as best you can. Link to comment Share on other sites More sharing options...
cjameshuff Posted July 21, 2011 Share Posted July 21, 2011 My question is what do you do to further stabilize your orbit when already at the circular velocity needed? If I'm at say 200km at my apogee above Kearth and the calc says I need to be going 2100.7 m/s to be in a circular orbit, and I am what do I do to change the fact that I'm continuing to rise and fall? Do I burn to change vertical speed? Is it actually possible to remain in a window the size of a few meters? Do we just not have the instruments to calculate this right now?You need to get periapsis or apoapsis at the altitude you desire, do this by burning to accelerate or decelerate on the other side of the orbit. You then do the exact same thing a half orbit later to circularize the orbit. You want to burn to set your velocity at periapsis or apoapsis, when your vertical velocity is zero. Real burns take time, and you'll end up with some vertical velocity at the end of the burn (ideally you'd start before reaching apoapsis or periapsis, but judging that is difficult with present instrumentation), but correcting the resulting near-circular orbit will take shorter and more precise burns.If you've got plenty of propellant, you can shorten this a bit by burning straight toward or away from Kerbin to zero out vertical velocity as you cross the altitude you desire...this puts you at periapsis or apoapsis of a new elliptical orbit, and you can then burn directly into a near circular orbit from there. This requires some faster and more precise maneuvering, though, and that initial burn is inherently less efficient than burning at apoapsis or periapsis. Link to comment Share on other sites More sharing options...
Sayle Posted July 21, 2011 Share Posted July 21, 2011 Yeah, I just get the velocity I want for the orbit then gently burn vertically to level out the orbit. It seems to but me in a fairly stable orbit - I had a variance of around 2000 meters. Link to comment Share on other sites More sharing options...
GeneKerman Posted July 25, 2011 Share Posted July 25, 2011 The first stable orbit I ever achieved was an eccentric orbit after overshooting my desired orbit, realizing I was above escape velocity, and panic-burning all my remaining fuel in an attempt to get back. The orbit stabilized hands-off with an apogee of 375,000-ish km, and a perigee of 51,000 km. I left the program running while the capsule was still headed deep into space (with the chute hanging out in hopes the capsule would reenter while I was gone) and when I got back home an hour later, the boys were still alive and still in space. The orbital period was about 47 minutes. After 8 hours, it was obvious that apogee and perigree weren't deviating more than 150m, so I shut it down. Link to comment Share on other sites More sharing options...
Tim_Barrett Posted July 25, 2011 Share Posted July 25, 2011 Floating off into space... Forever.... Link to comment Share on other sites More sharing options...
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