maltesh

I would suspect The Eccvecs are the three components of the Eccentricity Vector and the Hvecs are the three components of the Specific Relative Angular Momentum vector. Well done. The primary thing that I'd change is to return Mean Anomaly and Mean Anomaly at Epoch in radians. Mean Anomaly is more a quasi-angular parameter than an angle, and is more useful in the equations I've found in radians than in degrees. (Also, it seems to be that the Devs choose Mean Anomaly at Epoch UT=0.0 to have one of four values in radians for the celestial bodies: 0.1, 0.9, 1.7, or 3.14)

Some time ago, I wrote up a KSP Orbital Parameters Google Doc that discusses what the various values in the Orbit section of the persistence file mean, and how to adjust them to produce various results, as well as what needs to be adjusted if teleporting spacecraft off the launchpad is desired. For on-rails circular orbits, the least complicated way to space things out evenly through file-editing would be to adjust the Argument of Periapsis (LPE), which is the in-orbital plane angle measured in degrees from the ascending node to the periapsis. If the seven other Keplerian parameters (SMA, ECC, INC, LAN, MNA, and EPH) are the same , and the orbit is circular (ECC = 0) , distributing LPE evenly around 360 degrees (e.g., for each of three satellites, 0, 120, and 240 for EPH) will result in even angular spacing. Note: Back up the persistence file before editing. If you accidentally edit it in a manner that makes the file unreadable to the game, the game will blank the entire file.

KSP v.0.16 has a bug that afflicts all engines that have a Specific impulse rating in the VAB. What should happen is that, for a specific engine, fuel consumption should be directly proportional to the throttle fraction used: At 1/2 throttle, your fuel consumption should be 1/2 the rate of it would be at full throttle. 1/3 throttle -> 1/3 fuel consumption rate and so on. This results in a constant specific impulse regardless of throttle setting, which is the way it worked in all previous versions of KSP, and in general, in reality. In v.0.16, the fuel bug results in fuel consumption is proportional to the square of the throttle fraction used: At 1/2 throttle, you wind up using 1/4 the fuel consumption rate at full throttle. 1/3 throttle -> 1/9 fuel consumption rate. The bug results in an unrealistic higher efficiency any throttle amount below full throttle, and effectively infinite specific impulse and delta-V if you're capable of setting the throttle low enough. The bug is fixed in v0.17, and there's a makeshift fix in the addons section.

That looks a lot like the v0.16 fuel bug. Are you running the fuel bug fix?

I started watching with TNG about the third season or so when it aired. I watched DS9 as it originally aired, as well as Voyager, and eventually, Enterprise. As I recalled, DS9 wound up being my favorite, followed by TNG, then Enterprise and finally Voyager. I rewatched DS9, then Voyager, then Enterprise, then TNG at the beginning of this year over Netflix. Generally, Trek series tend to hit their stride about the third or fourth season. Enterprise had some incredible episodes in its fourth season, which is unfortunate, because that's the season it was canceled. I'd say that "In a Mirror, Darkly" is my favorite Mirror-Universe episode in the entire franchise. I also liked Voyager a lot better than I'd remembered. "Bride of Chaotica" is the best holodeck episode in the entire franchise. And the alternate versions of Voyager tended to be hilarious. "Living Witness" was an okay episode overall, but the reconstructed Voyager Incident in that episode was a hoot. As was the U.S.S. Vortex in the holonovel in "Author, Author." On the whole, both were decent shows. Though on the rewatch, I have become absolutely stunned that TNG managed to be renewed after the first season.

If you have a spacecraft that can do it, it's actually a lot easier to launch all the satellites on one spacecraft. Say you want four satellites spread at 90 degree angles around a single circular orbit. Calculate the period of that orbit. Calculate the semimajor axis of an orbit that is 5/4 as long as that period. Calculate the altitude of the apoapsis the longer orbit would have, if its periapsis was on the circular orbit. Ascend to the circular orbit. Circularize. Deploy the first sat. Burn to raise your apoapsis to the longer orbit altitude. When you get back to the circular orbit's altitude, circularize again. You're now 90 degrees behind the first satellite. Deploy the second satellite. Repeat for the third and fourth satellites, then return to Kerbin. Edit: Rereading the thread, I now realize that this is basically what togfox suggested in post #4.

If you have a spacecraft that can do it, it's actually a lot easier to launch all the satellites on one spacecraft. Say you want four satellites spread at 90 degree angles around a single circular orbit. Calculate the period of that orbit. Calculate the semimajor axis of an orbit that is 5/4 as long as that period. Calculate the altitude of the apoapsis the longer orbit would have, if its periapsis was on the circular orbit. Ascend to the circular orbit. Circularize. Deploy the first sat. Burn to raise your apoapsis to the longer orbit altitude. When you get back to the circular orbit's altitude, circularize again. You're now 90 degrees behind the first satellite. Deploy the second satellite. Repeat for the third and fourth satellites, then return to Kerbin.

It works for Kerbin to Distant Object with decent-sized SOI in a circular orbit around Kerbin. If you're doing a Hohmann Transfer from a low orbit to a high orbit, and the initial, low orbit is far, far lower than the final high orbit is, an object in a circular orbit whose radius is that of the high orbit will move about 63° in the time it takes you to complete the transfer. If you are in orbit over Kerbin at 100km altitude, the angular distance between the center of Kerbin and its visible edge is about 59°. The two angles are close enough to allow the Munrise/Minmusrise burn methods to work, when departing LKO to one of Kerbin's moons. It's also close enough to get you near the Moon when departing from LEO. Doesn't work for orptimally timing any other transfer. (Well, technically, if Kerbol had a visible surface, you could use it to time transfes to its planets, but you would need a spacecraft capable of several dozen kilometers per second of delta-V to get to a starting orbit where it would work.)

Circles are just ellipses with eccentricity 0, and a semimajor axis (and semiminor axis) equal to their radius. Almost anything that deals with ellipses will work with circles. Hyperbolas can get a bit tricky. It really depends on what you're doing with them. This would be the reference that was of most equational help when I was writing my orbital calculator. http://www.nature1st.net/bogan/orbits/kepler/orbteqtn.html This link was also pretty useful. http://www.braeunig.us/space/orbmech.htm And there's a Google Doc in my signature that does some discussion of the Keplerian Orbital Elements as present in the persistent.sfs file.

Took me a heck of a lot longer. I didn't have a good feel for how much fuel was left, so I was loath to orbit-scrape, and went for the old "outside track"method. Also was running the fuel-bug fix. Basically, what I did was sight across Kerbin's orbit, head to an orbital node, and match planes. Then it was a matter of pulling in the apoapsis, raising the periapsis, and riding the outside track. I went for a near-circular orbit that ranged from about 13,550 Mm to 13,580 Mm, to try to ensure that I'd pass through the 84,000 km radius sphere of Kerbin's SOI. Then it was the waiting game. Probably could have done some precise calculations with the Navball. Should have tried that. Ah, well.

Speed of light is approximately 300,000,000 m/s, not 300,000 m/s. In the paid version, this is not possible with any reasonable build. Even while sundiving, you probably won't crack 200,000 m/s.

For an unpowered orbit, velocity and altitude are inextricably linked. If you have a certain speed when passing a particular altitude going up, you'll have that same speed when passing that altitude going down. The orbital velocity required to punch through Kerbin's atmosphere at that shallow an angle and return to KSC is far in excess of Kerbin escape velocity at the surface. In fact, it's far in excess of Kerbol escape velocity at Kerbin's orbital radius. If you leave Kerbin's atmosphere with the required speed, you're not coming back to Kerbin.

As per the Wiki's article on Parts, the specific impulse on the RT-10 is 443 seconds.

As engines, the RT-10 solid fuel booster is pretty efficient. As fuel tanks, they aren't so efficient. The best full mass/dry mass ratio you can get using the RT-10 booster is just under 5:1. The best full mass/dry mass ratio you can get using stock 0.16 fuel tanks is 9:1. As a result, even though the sfrs are more efficient at burning, the absolute best that a single-stage of RT-10's can do is a delta-V of about 6,984 m/s. The absolute best that you can get out of a single stage of stock fuel tanks attatched to an LV-T30, the least efficient stock liquid boosters (assuming vacuum performance) is about 7,113 m/s.

Aye, the large impact basins tend to be smoother than the rest of the Mun (though the difference is a lot less in the paid version than in the demo). It may behoove you to build a very squat , wide-footed lander, so you don't have to care very much about the slipe of the terrain underneath the lander.

Definitely Venus. Stellarium is a great free program for answering the "What is that bright object?" question.

If you know the radius (rb) of the body you're orbiting, and your orbit is elliptical, you can get your orbit's semimajor axis from your periapsis altiude and apoapsis altitude. Your semimajor axis (a) is half the linear distance between those two points. rb is the radius of the body, and hap and hpe are the apoapsis and periapsis altitudes, respectively. With the semimajor axis, and the standard gravitational parameter(μ) of the body currently being orbited, you can find the orbital period (T). With the semimajor axis, the standard gravitational parameter of the body being orbited you can find the specific orbital energy (õ) of your orbit. And with the specific orbital energy of your orbit, you can find the speed (vs) that your spacecraft will have at any altitude (hs) your orbit takes it to. Some interesting things to note, here. Any two orbits around a body that have the same semi-major axis will have the same period, regardless of eccentricity. Any two orbits around a body that have the same semi-major axis will have the same speed at any altitude that they share.

Judging by the screenshots, he's definitely (presumably unknowingly) exploiting the fuel bug.

MB-Ruler is a free-for-personal-use on-screen ruler with protractor capabilities. I've had it on my system for awhile, but the only thing I've ever used it for in KSP so far is confirming Minmus' axial tilt.

When I don't physically attatch the chute to the pod, my solution is generally, "Aerobrake." Come into the atmosphere with a periapsis height of 10 km or so, that can burn off over a dozen km/s of velocity. Then don't pop the chutes until you're nearly down. Over oceans, I've been known to wait until about 1000m, but generally, I wait until the speed has dropped to under 350 m/s or so.

Well, since you did my challenge, figured I might as well return the favor. Yeah, I mechjebbed this one, and , unfortunately, didn't take as many screenshots as I'd like to have taken. Jeb was on board at 3:55 after launch, and returned to Kerbin after 2 days, 06:15.

I've never headed out to it on an escape trajectory. I head into an elliptical orbit that tries to put the apoapsis on the Disasteroid's trajectory at about the time that the Disasteroid will be nearby. As the google doc indicates, if you're really exact, you can intercept it at about 19 hours after launch. The mission feels like it's doable with a Munshot craft, but I've not tried it with one, as I like having more fuel and RCS than I typically build into those.

I'm afraid you're incorrect here. You can save large amounts of fuel by taking advantage of the Oberth Effect, and burning from low orbit into a trajectory that allows you to coast directly into your transfer orbit. For instance, consider a spacecraft starting from a 100km Kerbin orbit, going at about 2.1 km/s. Assume you want to get it to escape Kerbol. (Escape velocity at Kerbin's altitude, about 13.1 km/s) To run that spacecraft up to Kerbin escape velocity from that altitude (about 3.2 km/s) requires a delta-V of about 1.1 km/s. That will put you just outside Kerbin's SOI at rest relative to Kerbin, moving at Kerbin's orbital velocity of 9.3 km/s, and you'll need a delta-V if about 3.9 km/s to reach Kerbol escape. Total Delta-V from 100km orbit by burning to escape, then escaping and burning to Kerbol escape velocity, about 5.0 km/s. Instead, let's take advantage of the Oberth affect, and burn up to about 5.0 km/s from that 100km orbit, (Delta-V 2.8 km/s) timed so that we cross the SOI boundary, we do so in precisely the direction that takes us across the SOI boundary moving in the direction of Kerbin's orbit. When we cross the SOI boundary, we'll still have 3.2 k/ms of that velocity with us, which, when added to Kerbin's orbital velocity, takes you on Kerbol escape. Total delta-V, 2.8 km/s. In this case, a 44% saving in required delta-V to reach Kerbol escape, which results in very significant savings in fuel and corresponding spacecraft mass. When going from Kerbin to interplanetary destinations, in almost every case, you wind up with significant fuel savings by burning directly into your tranfer orbit from as low a Kerbin orbit as you can manage.

I usually go with three-footed landers, but I tend to spread the legs very widely. Probably could have raised the legs a bit higher on that one, for even more stability.

Well done. To my knowledge, you're the first other person to attempt the challenge that's actually managed to rendezvous with and destroy the disasteroid. I should probably do some kind of leaderboard thing. Do you remember how high you were, or how much time it took?