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About Zhetaan

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    Rocket Scientist

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  1. On the one hand, there are a few missions that require more experience. On the other hand, doing them is how you acquire experience. On the gripping hand, frustrating yourself unnecessarily makes things less fun. Along with @18Watt, I agree that Moho is probably a bad choice if you are, as your post title suggests, a 'low-skill player'. Putting aside the issues of simply getting to Moho in the first place, landed equipment on Moho generally needs alternative power arrangements and such because of the length of night. Vall and Laythe are both good choices and have different require
  2. While many kerbals may yearn to see the stars from beyond their sky, the singular terrors involved in actually doing so are such that wishing to repeat this unlikely stunt is reserved for only the truly certifiable, such as Jebediah. Put another way, consider that these are the same companies that supply the explosion-worthy parts who are also asking you to loft the tourists. Perhaps these contracts are a disciplinary measure for corporate employees who are somewhat less than VI in their VIP. I know that I work with some people who could use a twelve-year holiday to Jupiter--then I migh
  3. If you are writing of what I think you are, then it's not a bug. The scanner module shows extremely low-resolution data, but that data is also shown on a per-biome basis, whereas the Tracking Station shows that data on a per-celestial-body basis. Differences are to be expected, and the values that you get still won't be very accurate: in essence, the orbital scanner is really only good for a qualitative test that tells whether the resource is present or absent, not a quantitative test to tell you reliably how much is there. You'll need to get on the ground and use a surface scanning module
  4. These sorts of problems are difficult to diagnose without a picture of both the craft and of exactly what you're trying to do. However, the usual suspects in these sorts of cases, as @steuben and @FruitGoose have already mentioned, are autostrut and part clipping issues. Does everything explode at once, or does it tear itself apart over a few seconds? The autostrut problems normally occur when you have an autostrut set to the heaviest part, and the identity of that part changes mid-flight, or when you have them set to the root part and you change that part (usually when you undock somet
  5. Sorry about that. Even with all of the simplifying assumptions that KSP makes with respect to physics, there's still a lot going on. KSP attracts a lot of intelligent people who want to understand some of the technical depths (including you: you did ask the question, after all) so perhaps it was inevitable. For the purposes of directly (and briefly!) answering your question, lower is better, except in certain very specific circumstances.
  6. I never bought into the idea that everything KSP needs to have an added K. I was honestly disappointed when the contracts appeared requesting Kolniya orbits, since Molniya orbits are a real thing and for the sake of clarity, I think that it's a bad idea to confuse legitimate terminology--especially when people who don't know about Molniya orbits wouldn't be in on the joke. Imagine if KSP insisted on calling the point of closest approach on an orbit the keriapsis--or that flyby trajectories were kyperbolic. That being said, I'm not immediately averse to the idea of Kerbin's star having a
  7. Not to compound the pedantry (sorry; I couldn't resist), but my example was to illustrate that the benefit of periapsis kicks over a single burn does not come from the Oberth effect. Yes, as the apoapsis rises higher, the speed at each periapsis encounter for subsequent kicks increases, and therefore the Oberth effect also increases; however, these increases occur whether you do it in one burn or in ten. The principal benefit of doing periapsis kicks is that it allows one to concentrate the manoeuvre in space (at the cost of time) at the periapsis, thereby coming closer to a practical re
  8. @camacju: While avoiding an atmospheric dive is certainly helpful, the main benefit of periapsis kicking is that it reduces cosine losses: for this reason, periapsis kicks make sense for low-thrust craft even when they are not at risk of falling into an atmosphere, and they also make sense for high-thrust craft that need to make very long burns (for whatever reason that they may need to do so--escaping the star, perhaps). This comes of the fact that velocity is both a magnitude and a direction, and when thrust is low, the burn takes so long that the direction can change substantially
  9. It's a little more complex than a simple higher/lower choice. Yes, as others have said, the Oberth effect is important and yields great returns for expended propellant, but there is more going on than a straightforward relationship of 'go lower = go faster = go better'. One thing to keep in mind is that there are different requirements for different destinations. In order to make an interplanetary transfer, you need a specific hyperbolic excess velocity that is different for each planetary destination (and different for each transfer window, too, owing to inclination and eccentricity va
  10. I have to admit that the gravitational parameter is just about the last thing I would think to check, too. I'm glad that you figured it out. I don't know whether desmos can do this, but Newton's method works just as well on the hyperbolic form of Kepler's equation as it does on the elliptical form. I know that it can be calculated, but I do not know whether it is easily iterated, let alone automated.
  11. That seems to me to be an asymmetric thrust problem. You'll need to turn on the centre of thrust indicator in the VAB and ensure that the line coming out of it points through the centre of mass. It's a bit tricky to do since the line doesn't come out of the front of the marker, but you can do it by rotating the view of the vessel while in the VAB. Before you get that far, be certain to remove any boosters that will be expended before you light the OMS engines; you don't want to include engines that will be staged away by the time that the OMS fires because they and their tanks will thro
  12. FlybyFinder won't do multiple passes of the same body. It can calculate a J-D-K-D trajectory, for example, but not a J-K-K-D trajectory. It has to do with the fact that solutions to Lambert's problem break down when considering transfers from a point to the same point (actually from a radial distance from the centre of attraction to the same radial distance, but it's the same issue as in a repeat flyby). There are ways to perform that calculation, but I've found them all to be far less than user-friendly. Were I given the choice, I'd exhaust the possibilities with the J-K-K-D path
  13. You considered using a Duna flyby to raise your periapsis after all of this; after two Kerbin flybys to get your solar apoapsis down to Duna's altitude, it makes sense--provided that you have the life support--to use Duna to raise your solar periapsis so as to slow your velocity on your next encounter. I went a little mad with FlybyFinder and a J-K-E-D trajectory, that being roughly what you initially proposed. My numbers largely agree with yours; I haven't yet found a way to get the braking delta-V down to a manageable value for your vessel. However, the most efficient assist trajectory I
  14. I thought that the impracticality was implied by the 5 centimetre acceleration. You have my apologies if that was not clear; to be unequivocal, though, allow me to state for the record that you certainly won't see me trying to push a kilotonne craft with only one Nerv engine, whether at Gilly or anywhere else.
  15. Gilly's surface gravity is .049 m/s2. The Nerv has a thrust of 60,000 N. This would mean that a Nerv can, at least theoretically, land a craft of anything up to 1,224.5 tonnes, though for a safety margin it's probably best to limit the weight to 90-95% of the thrust. It'll still take a long time (a Nerv pushing that mass will have the same acceleration as Gilly's gravity, so 5 cm/s2), but you're underrating the Nerv by a factor of about four.
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