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Iskierka

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About Iskierka

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  1. I have noticed this on a Lynx rover without using Bon Voyage at all, so at most this is likely exacerbated by BV, not caused. It's much less extreme in my case, but definitely there across about half a dozen loads to travel further, and slowly growing. Additionally, when launching this resupply pod back to Kerbin, I had an odd issue where around 20-25 km away it would suddenly crash into ParallaxColliders, resulting in complete destruction, as well as teleporting the rover nearby and *also* colliding that with ParallaxColliders. I was able to resolve the situation by driving the rover a
  2. In that regard, I think the simple wikipedia svgs represent the trajectory poorly - the UVIS diagram shows periapsis being before noon, indicating it was a descending trajectory in solar frame. Given it's close to noon though, I'm not sure there's much boost - its purpose may be more to ensure that it can cross paths with Earth for a big boost that Venus could not provide easily. Still a valuable flyby to have.
  3. Sorry to contradict you so completely, but the 1999 flyby was almost perfectly on the light side: Subsolar point, as google will tell you, is noon. Periapsis is within three "timezones" of the subsolar point. Completely light-side. Can't find details on the 1998 flyby, but that's the one you were uncertain about, and you were wrong about the one you were certain of. As for being able to do a dark-side flyby in stock ... It's in complete stock system, but it's close enough to the real system in ratios for all conclusions to be transferrable. It also starts the worl
  4. The magnitude does not change appreciably under any physical model. This is the point of conservation of momentum. In fact, neglecting the body's part of momentum exchange increases the desired velocity change in the solar reference frame, as it would, insofar as is meaningful, move the body in the opposite direction to what you desire, while your receding velocity will not be changed, thus being pulled back with the planet as its velocity change subtracts from yours. If the trajectory described that you wish to execute is possible at all, it is possible in Principia, despite having only
  5. Or to clarify, it would not be possible to have meaningful momentum exchange even with celestial bodies not being on rails; even the largest Kerbal rockets are completely dominated in mass by the smallest bodies. This means that, even locking momentum of the body, so there is no exchange, there is negligible, or likely nonexistent difference with the fully simulated case, given computation precision limits. Do note that while there isn't momentum exchange, there is momentum change for the satellite; we can violate conservation here with no real consequences for the accuracy of the simulation,
  6. The problem with simplifying it this way is that g-force did not cause the pogo oscillation; it would not be prevented by shutting down two outboard engines, or shutting down one and gimballing to compensate. It's specifically the inboard engine that suffers and must be shut down, independent of what the acceleration is, and was a problem but tolerable from ignition to CECO. While limiting stress would potentially be an argument for the lower stage, it does fall flat noting, again, that the second stage has CECO at very low acceleration. This is a localised problem to just that engine tha
  7. Irrelevant, because the g-force measured is the acceleration of the rocket; as it is in no way connected to the ground, gravity does not influence experienced forces, as all things are falling uniformly, and the only non-body-force is that of the engine's thrust. The F-1 engine would also be capable of throttling with minimal modification; the required pieces of flow control valves, flow sensors, and control feedback systems were already all established in the engine to maintain proper operation at a fixed throttle. The only modification required to get some throttle capability would be a
  8. The point is that the evidence still points to the exact same patterns of mixed scale/feather as we've seen in more complete but smaller tyrannosaurids. And regardless of scales or feathers, they're birds, not reptiles. https://en.wikipedia.org/wiki/Avemetatarsalia contains both all dinosaurs and all of the families that are popularly thought of as dinosaurs but not actually dinosaurs. The argument of size against insulating layers also fails as feathers are not purely insulating layers, as seen from the fact birds are mostly covered in feathers regardless of the temperature of their typical h
  9. You posted previously in the Otter submersible thread, which has been packaged into the Exploration pack and so is not updated. If you have the USITools version from that, you are not running the latest version. Delete USI Tools, download USITools itself fresh from the catalog page, and install that.
  10. "Most high TWR craft" is very few orbital rockets, however. In fact, I can only think of a few to be all-solid first stage (two to have flown, at the moment. Might be a couple more), when I could give a huge list of all-liquid launch vehicles. It's also incorrect to say that solids don't have heavy engines - as the entire container is an engine, and the entire thing must contain the pressure of the burn, solid booster casings are very heavy, are very dependent on the thrust they produce, and likely work out worse than liquid engines. The advantage of solids is they're cheap so it doesn't matte
  11. Important note that this is a true but naive description that assumes flat surfaces and directly what is absorbed/reflected by the material. Vantablack is not a (very) good absorber as a material itself, as it is just carbon nanotubes. Vantablack is so black because the nanotubes are stood on end and any light they reflect bounces inward, into the forest of nanotubes, and will eventually be absorbed by something far more often than it manages to find its way back out again. Because of this, Vantablack is a major exception to the rule and is also a very bad emitter - any light it tries to emit
  12. Those are KSP Interstellar radiators, by the right-click menu. The mod as a whole can be ... wonky, and doesn't like to use stock mechanics, which NF does for heat and such. Use a radiator that doesn't have the wasteheat resource assigned and try again.
  13. The rule of thumb given here is one megawatt per kilogram (of ship), nothing to do with Isp. We can, however, infer Isp from that. Assuming an acceleration limit of 5g, we have 10 MW/kg / 50N/kg = 1 MW / 50N, which equals 20,000 m/s. A quick sanity check on the definition of thrust power ( P = Tv/2 ) tells us we need to double this to get the actual exhaust velocity, but this is only 4,000 seconds still, and qualifies as a torchship. To qualify as a torchship at 1g, we can now quickly infer an exhaust velocity of 20,000 s (multiply by 5). Very high, but not ludicrous for the kinds of tech
  14. The point of methane is it's only mildly cryogenic, and therefore fairly trivial to store long-term anyway. Cryogenic power requirements are, frankly, quite tiny if you plan them from the start. At 4:1 it is also probably the best ratio of hydrogen other than hydrogen itself, and high enough that it likely has better volumetric hydrogen density than most other options, despite having a low density itself. Of course, all of these suggestions are terrible if you are looking to use hydrogen as hydrogen in-flight, as they all require considerable power and heavy machinery to extract the hydro
  15. It may be somewhat more compact, but that is an absolutely dreadful ratio of hydrogen by mass, which is the only thing aircraft or rockets care about. Methane is considerably better and nearly as workable, if you must find a way to make it denser. Nitrogen and boranes also sounds like a good combination for high toxicity and instability, though ammonia borane itself is apparently stable, you're gonna get nasties around it with repeated heating and reacting.
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