UmbralRaptor

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  1. In KSP, rockets are easy while compute is limited. In real life, compute is plentiful and rockets are hard. So going through a bunch of simulations to save a few hundred to a few thousand m/s actually gets you significantly more payload for little effort. There's also an upper limit to how much velocity you can gain from a single slingshot (it decreases with faster and more distant approaches to a planet), which pushes towards a handful of bodies and multiple passes. FWIW, My back of the envelope calculations are that from a 200 km Earth orbit, you need 5375 m/s for a Hohmann transfer to Venus, and 7236 m/s for a Hohmann transfer to Jupiter. But just getting to orbit tends to cost 8-9 km/s...
  2. You can redownload KSP from the website by logging into your account and selecting Download. (I'd suggest the zip so you can unzip and copy over the fresh parts folder)
  3. How does Triton feel about Neptune getting a second large moon?
  4. It's probably suffering from poor pitch authority, given the the butterfly tail has all the control surfaces well back/forward of the center of mass. It's somewhat hard to say with the center of lift and center of mass icons off, but there's the possibility of it being tail-heavy/unstable in some configurations. The off-axis thrust is potentially also an issue. Playing around with some alternate configurations, I got this thing (which is probably rather overweight for flitting around, and presents some entry/exit issues.
  5. Pretty much. We need to step through the launch burns (since they are not instantaneous) to get the final orbits. And depending on what the final orbits are, an algebraic solution may not exist. Okay, this helps enormously because of the assumptions that they have the same semi-major axis, orbit orientations such that they are most distant from each-other at apoapsis, both are at periapsis at burnout, and both are at periapsis at the same time. This will require some explanation. Most fractions of an orbit are a huge hassle to calculate. Full ones are easy, and it takes exactly half an orbit to get between periapsis and apoapsis. But beyond that, you get into the messy realm of converting between mean anomaly (time, sort of), eccentric anomaly, and true anomaly (actual position along an orbit). If the initial orbits are sufficiently different, the maximum distance on the first orbit will have one (or neither!) ships at apoapsis, so will require calculating intermediate distances. For orbits exactly opposite of each-other with different apoapses/periods, you could still get times given the known start positions (something like 1.5 orbits for one and 2.5 for the other. Exact values depend on the orbits) The only easy(ish) part is finding some orbital parameters after burnout (given the above assumptions): Ap + Pe == 2a Ap = (1+e)*a Pe = (1-e)*a Energy = v^2/2 - GM/r = -GM/(2a) T^2 = (4π^2/GM)*a^3 Where r is current distance, v is current velocity, e is eccentricity, a is semi-major axis, GM is the planet's mass*gravitational_constant, and T is time.
  6. Barring something extremely nice in both how those rockets are accelerating, this will require messing around with numeric methods (eg: using numpy or excel). First to find their trajectories at burnout, and then possibly to deal with the way that Kepler's equation cannot be solved analytically.
  7. More updates: Searching for Borisov's origins: the best guess is unlikely, so it may have been floating around for quite some time - https://arxiv.org/abs/1912.10213 Borisov may have formed from an AGB star o_O - https://arxiv.org/abs/1912.12730
  8. There's a reddit based one. Incidentally, there's also an IRC channel (#KSPOfficial on esper.net)
  9. It (and the associated DLC) are on sale on both Steam and GOG right now. If you're looking for something a bit more formal, I can suggest a website or a textbook.
  10. No, that's correct. ΔV to LKO is less than the effective exhaust velocities of some engines.
  11. Local university is doing an event, though the weather is very questionable. (That typed, there are plans for streaming video if the clouds are uncooperative)
  12. This IIRC rapidly gets you into territory where there are no analytic solutions. You'll want to use a numeric integrator for the burn (eg: writing a script in Python) to work out how long the burn time is, and what sort of angle the ship will pass through. I suspect that you can tell on success *before* SOI transition by working out the transfer with patched conics, and when your specific energy (0.5*v^2 - GM/r) reaches that.
  13. Note that for our purposes, Venus and Mars are "Earthlike", so be careful not to take "habitable" too literally. You might think so, but it totally works for KELT. WASP and TESS aren't *that* much bigger, also.
  14. Kind of a bump/update: some people determined what it would take to intercept C/2019 Q4: https://arxiv.org/abs/1909.06348 Anyone got a spare HLV?
  15. Those tend to be fit with parabolas, and depending on reference frame may only have an eccentricity above 1 once you have a bunch of sig figs. For example: https://en.wikipedia.org/wiki/C/2006_P1_(McNaught) Anyway, the 3 highest eccentricities: C/1980 E1 (Bowell) at 1.0575, 1I/ʻOumuamua at 1.19951, and C/2019 Q4 (Borisov) at... still being determined but probably above 3.