• Content Count

  • Joined

  • Last visited

Community Reputation

854 Excellent


About Zhetaan

  • Rank
    Rocket Scientist

Recent Profile Visitors

4,141 profile views
  1. Fair enough. There's also a K-E-K-K-J trajectory that more or less gets everything that you can get out of repeated Kerbin flybys before you reach maximum velocity (and minimum assist), but just the paths I showed you earlier involve waiting a bit over two years between the Eve and the second Kerbin encounters; a third Kerbin encounter would add another two years to the flight time (or three; I don't remember). Do note that course corrections probably are not so bad as you fear; Eve and Jool are both inclined but still arguably in the plane of the solar system, and the flyby paths are designed to be flown on inertia alone. You'll need some manoeuvring reserve for corrections anyway, but the essence of it is that after the big burn at Kerbin, you don't light the engines again until Jool (or later). Most who fly these paths well use less than 100 m/s total for corrections, and most of that is in RCS. But there is, as usual, the trade-off between efficiency and time, and if you want to move more quickly, Duna is certainly an option. It will still take time (windows between Kerbin and Duna occur somewhat infrequently because they are next to one another in orbit) but it's a viable, albeit unusual, choice. I will suggest that you consider refuelling at Ike instead, though. The lower gravity and lack of atmosphere could be great helps to you.
  2. I queued some Flyby Finder trajectory searches for you; a K-E-J assist window occurs approximately every 400 days, starting at day 0 (though the best assist that I found was at day 776). I neglected to post any of them because they all required, at a minimum, 3,170 m/s of delta-V to get a Jool flyby. The problem is that for Eve to raise your apoapsis to Jool orbit in one pass, you need to supply most of the energy yourself in the initial burn because the amount of velocity change that you can get from Eve is capped by Eve's own velocity. If you need more than that, either because you're going farther away or because you're approaching at an angle or speed that is less than ideal, then you need to get orbital energy from somewhere else. One place that you can go for that energy is Kerbin: the K-E-K-J trajectory is much better. I found quite a few paths that reduce your delta-V to less than 2,000 m/s. Here is a selection: Path Start Day 1st (Eve) Encounter Day 2nd (Kerbin) Encounter Day 3rd (Jool) Encounter Day Total Time (days) Initial dV (m/s) 1 1374 1564 2433 3187 1912 1338 m/s 2 1384 1568 2438 3168 1784 1358 m/s 3 1408 1568 2432 3249 1841 1621 m/s 4 1424 1572 2428 3235 1810 1920 m/s For the first path, you'll need to start from an inclination of -2.6° and 75 km Kerbin orbit. The path takes you to 120 km altitude at Eve, 284 km at Kerbin, and 1000 km at Jool. Please note that these paths all lead to Jool, but not past Jool; for obvious reasons, Flyby Finder does not calculate trajectories to open space. However, tweaking the encounter with RCS in order to tease out an assist to deep space is quite possible.
  3. That's interesting; mine clearly do. In lieu of a charge rate, they display, 'Broken!' In fairness, I also run Kopernicus which uses its own solar panel code for purposes of pointing at multiple stars, so it's possible that the unequivocal message is a part of that code. I'll have to check. As to the code that you copied: deploystate = EXTENDED is the part that fixed the panels.
  4. Each broken solar panel in the vessel will have a line in the save file that says something to the effect of (and I do apologise for not knowing exactly, but I'm not near a save file that I can test): STATUS = BROKEN. It could be DeployState = BROKEN--the point is that BROKEN is the key word. You'll need to change that line to say either EXTENDED or DEPLOYED--again, I don't remember which, and you'll want to check a known-good OX-STAT-XL to know for certain--but that will fix the panels. The large OX-STAT panels do not have a visual indicator of their damaged state, unlike the extendable panels that shatter when broken. The only way to know for certain whether they are working is to check the part action window and see whether they are capable of generating charge. Broken panels will have a status message of 'Broken!' in the part action window.
  5. It's been a bit under four years. Squad added green monoliths in v1.2, and to my knowledge, green monoliths have always had this tech node unlocking behaviour.
  6. Wouldn't that address your ballast problem? Actually, with respect to both your propeller and your range problems, you might be able to get better results by trying something more like a bathyscaphe than a submarine. I say this from a purely theoretical position, of course, so you'll need to do the testing, but you could design a vessel that is neutrally buoyant at something less than full tanks of ore. You can take wheels, Wheesleys, and some amount of wing to keep off the seafloor (probably trivial because you can tailor it so that buoyancy cancels most of your weight), explore the ocean bottoms, and when you start running low on fuel, begin converting ore. As you gain positive buoyancy, you also gain fuel and can use that to make your way to somewhere that you can mine to recover ballast and dive again. Also, I believe that fuel floats but I do not know whether the tanks float higher without fuel--i.e., I don't know whether the empty space is properly accounted, so I don't know what effect burning the fuel would have on your buoyancy. It's not a working propeller but it might be a place to start.
  7. Oh! I misunderstood earlier; you know that it's Day 82, but in case you forget again, you need a way to determine that Day 82 is the day that you want without needing to memorise it or rely on pre-calculation. In that case, I can think of two answers. The first is to use manoeuvre nodes to plot an orbit that just barely leaves Kerbin's sphere of influence, set up a transfer to Moho's ascending node, and note the time-to-node. That is subject to inaccuracies because the thing in solar orbit is necessarily not precisely in Kerbin's orbital track, but it's probably close enough. The only way I can think of to get more accurate using in-game tools is to plot an escape burn to Moho's ascending node altitude and start pressing the + Orbit button until you get a burn that actually goes there. You'd need to tweak the node location in order to keep your escape pointed Kerbin-retrograde and you'll likely get joint fatigue in your knuckles from all of the clicking, but it should work. This depends on having something in orbit that you can use to plot these manoeuvres, whether it's your Moho vehicle or a random low-orbit satellite, but reference rockets that you put in orbit are arguably in-game tools, so there it is. Granted, you asked for fast, not accurate, but aside from setting this up in advance, I can't think of a faster way using only the in-game tools. This is a situation where you're getting a good answer for the wrong reasons. In fact, the only reason that this works is because Kerbin is in a zero-eccentricity, zero-longitude-of-ascending-node, zero-argument-of-periapsis orbit that can thus directly relate the true anomaly value of Moho's longitude of ascending node to the mean anomaly value of its own orbital position without any correction at all. However, Kerbin starts at π radians at epoch, not zero. The reason it works anyway is because it sets up a transfer orbit: you want to start on the opposite side from the destination, so adding π radians is a necessary step. If Kerbin had had any other starting location, then this would not have worked.
  8. Since you got a departure date of day 82, wouldn't the subsequent windows for this method be multiples of 426 days (one Kerbin year) after this date? You're not transferring directly to Moho, but rather a point on Moho's orbit, and since that is a fixed orbit without perturbation, there's no synodic period: Kerbin will pass its ideal alignment with that point once every year.
  9. I suppose you're right that I shouldn't assume others will take a non-rotating reference frame as a given. Further, you are correct that older versions could not handle dates after a century or two. Escape velocity from the sun at Kerbin's altitude is given by: vesc = √ (2μ / r) vesc = √ (2 [1.1723328 x 1018] / [13,599,840,256]) vesc = √ (2.3446656 x 1018 / 13,599,840,256) vesc = 13,130 m/s An eighty-year solar orbit with a periapsis at Kerbin has a semimajor axis of: a = 3√ (μT2 / 4π2) a = 3√ [([1.1723328 x 1018] * [9203545 * 80]2) / 4π2] a = 3√ [([1.1723328 x 1018] * [5.4211353962896 x 1017]) / 4π2] a = 3√ (6.355374838311 x 1035 / 4π2) a = 3√ (1.609835252771 x 1034) a = 252,499,474,052 metres And an apoapsis of: a = 252,499,474,052 metres 2a = 504,998,948,103 2a - Pe = Ap = 504,998,948,103 - 13,599,840,256 Ap = 491,399,107,847 metres, which is a bit over four times beyond the apoapsis of Eeloo (note that this is true apoapsis, not surface altitude). The periapsis velocity of this orbit is: v2 = μ * [(2 / r) - (1 / a)] v2 = 1.1723328 x 1018 * [(2 / 13,599,840,256) - (1 / 252,499,474,052)] v2 = 1.1723328 x 1018 * (1.4310014659636 x 10-10) v2 = 167,760,995.5397 v = 12,952 m/s Which is 177 m/s less than escape velocity at that altitude. It would take very little to push this orbit to escape, so your recollection is probably accurate.
  10. I believe that it will disappear if the ship is still connected to it; asteroids are treated as a special category of vessel parts, so they are recoverable. I don't know whether they are worth anything. Be certain to disconnect any clawed parts and recover them separately if you should want a decorative rock accessory for your planet.
  11. In reality, an orbital speed of zero occurs at the 'endpoint' of a parabolic trajectory. If there is any excess velocity, then the trajectory is hyperbolic (and in fact, the velocity beyond what is needed to escape is actually called the hyperbolic excess velocity), and if there is insufficient velocity, then there is an instantaneous point where the velocity is zero in the vertical direction (you're more familiar with that point as the apoapsis), so there is difficulty already in this because a parabolic trajectory is a pseudo-stable solution to the equation. In other words, if you have any excess velocity beyond escape velocity, then your speed will never go to zero; it will go to whatever the hyperbolic excess is. So to answer your question, no: there is no stable orbit with zero velocity. At best, it is a pseudo-stable co-orbital relationship where a nudge in any direction will either close the orbit or result in escape--and fun theatrics with Lagrange points don't count because those involve orbit about a third body. In terms of the game, both infinity and zero are a bit more discrete. On the one hand, there is an absolute limit to how far you can get from the sun before you have an addressing error in the coordinate system, and on the other hand, there is an absolute limit to the possible precision of a floating-point decimal such that the rounding errors will leave you with the wrong velocity. On the gripping hand, you can probably get a good approximation out at the fringes of available space.
  12. At a minimum, your minimum inclination must be the same as the latitude of the waypoint, or else you'll never reach it. There are some disadvantages to doing that rather than using a polar orbit: you'll only touch the waypoint at the highest latitude, whereas a polar orbit gives two chances (one on each side of the planet). The other thing to remember is that you need to account for orbital resonance. Kerbin rotates once in six hours, so it rotates at one degree per minute. Your orbital period is 31 minutes, which is very, very close to a resonance; your orbit track moves across the surface of Kerbin at a rate of one degree per orbit. Of course, Kerbin itself rotates thirty degrees in that time, so to cover all of the planet, it's going to take a while. There are none I know that will project your track onto the planet, but ScanSat will project it onto a map of the surface, which is of equivalent value. Furthermore, it will project your equator crossings for the next 100 orbits and give you an idea of whether you're in a repetitive resonance or whether you'll actually cover the whole of the surface. If you'll look at this image that I pulled from the ScanSat Readme, you can see the blue and orange tick marks at the equator. Blue ticks are crossings going north and orange ticks are crossings going south; the spread and even distribution shows that the orbit is not resonant. If the ticks seem to bunch together into groups of five or six, then that indicates a strong resonance, and that means that you'll only ever cross the equator at those points; in other words, you'll pass over the same ground again and again without going to new territory. That's great if your waypoint is on your orbital track, because you'll have many chances to get the right encounter and run your tests. It's terrible otherwise.
  13. This is my shortlist: Near Future Propulsion: Includes the Cryo Separator part that will strain xenon gas from the atmospheres of some planets. However, the xenon is not generated by this mod, but rather by the bundled dependency Community Resource Pack. The base implementation includes a 50% chance of being present in any other atmosphere and guaranteed presence in Kerbin's atmosphere, Kerbin's Water, and Laythe's Crater Bay--you have to mine the ground in those biomes; it's not in the water. Although it is extremely inefficient to strain Kerbin's atmosphere for xenon (for the most part, Kerbin resources are more for testing purposes than anything else; you can simply buy most resources in the VAB, after all), xenon is expensive enough that it may be worth it, provided you're willing to be liberal in your use of time warp. Near Future Electrical: Includes the Nuclear Recycler part that can generate xenon from depleted nuclear fuel. The problem with this is that it requires you to have a source of depleted fuel; i.e., a nuclear reactor. Nuclear reactors are heavy, expensive, and require a lot of radiators. USI Reactor Pack: The link is to MKS, but there are, I think, several mods that make use of the USI Reactor Pack. So far as I know, it is not available as a stand-alone mod but is a hard dependency for a few other USI mods, MKS being one of them. These reactors are designed to give off a tiny amount of xenon gas as a side product. Of course, like the Near Future reactors, these are neither lightweight nor cheap. Community Resource Pack: This mod does not include the parts needed to obtain resources; however, for most crustal resources, special harvesting parts are unnecessary because the stock drills serve adequately. This includes asteroidal xenon, which has an 80% chance to appear. I have not tried Xenon ISRU or any others. You may notice a certain bias towards Community Resource Pack and asteroidal xenon. From this list, it really is your best option. ... Aside from more conventional propulsion, that is. To be completely honest, a reusable crew shuttle that also makes a point of using the most expensive and difficult-to-obtain resource in the stock game seems to me to defeat the purpose. However, I say that without judgment; it's your game. On the other hand, it's also your stranded crew.
  14. Nicely done. Going to Eve was the best thing you could do. Congratulations on figuring out how to save the mission!
  15. In fairness, you can do that without the MPL or contracts if you're willing to grind a bit.