metaphor

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  1. In case anyone wants to replicate the newly "discovered" Planet Nine, in your RSSKopernicus.cfg file copy the entry for Neptune and replace the start of it with the following (you can change the name): name = Persephone finalizeOrbit = true Template { name = Jool } Orbit { // Target body name: // Center body name: Sun (10) // Center-site name: BODY CENTER referenceBody = Sun semiMajorAxis = 75900000000000 eccentricity = 0.58 inclination = 20 meanAnomalyAtEpochD = 148 longitudeOfAscendingNode = 100 argumentOfPeriapsis = 151 color = 0.19215, 0.33333, 0.56862, 1.0 } Properties { description = Discovered through its gravitational effect on the farthest bodies in the solar system, Persephone is slightly smaller than Uranus and Neptune. radius = 21000000 // adjusted below average to approximate height where pressure approaches 1000 Bar mass = 6E+25 rotationPeriod = 36000 tidallyLocked = false initialRotation = 0 isHomeWorld = false timewarpAltitudeLimits = 0 5000 30000 30000 100000 300000 600000 1000000 // FIXME add biomes ScienceValues { flyingAltitudeThreshold = 191000 spaceAltitudeThreshold = 3000000 } }
  2. Yeah, that happens sometimes. If you want to fix it, put a maneuver node down on the orbit after the encounter. This will force the game to compute the next orbit and should show you the second encounter.
  3. Giving a range is a good idea. Here's some new charts with a range of values:
  4. The mass of the real NERVA was about 6.8 tons, for a vacuum thrust of 333 kN and Isp of 850 s. There were also other nuclear engines in planning, like the SNTP (Space Nuclear Thermal Propulsion) program, which had an engine with a mass of about 1.6 tons, a thrust of about 120 kN, and an Isp of 930-1000 s. More info
  5. I just got a lander very similar to yours into 60 km orbit for about 1550 m/s from 2700m altitude. But you're right, the atmosphere of Duna is very thick now for small unaerodynamic craft, a lot thicker than in 0.90, even at 30 km altitude. edit: with the 1.0 aerodynamics it took about 1380 m/s to get into 60 km orbit with the same lander.
  6. Drag losses can be very different between large, thin rockets and small, fat rockets. Drag force is proportional to the surface area that goes into the windstream. The acceleration due to drag (i.e. delta-v losses) is drag force divided by mass. For example, a 1.25m ship will have twice as much drag losses as a 2.5m ship that has the same shape but scaled up.
  7. Yep. For ascent from atmospheric bodies, I just tried some ascents experimentally to come up with delta-v values. It depends a lot on the size and shape of your rocket (and on the heat tolerance of your parts), even assuming that you fly the perfect gravity turn. Orbital maneuvers in vacuum can be calculated, atmospheric maneuvers not so much.
  8. You can capture propulsively into Eve orbit for less than 200 m/s usually. (how to get to Gilly easily) Capturing at Jool also takes about 200 m/s or less, or can also be done for free by a gravity assist from Tylo or Laythe. Aerocapture is not performed in real life because it's usually just not worth it. The heat shield needed has similar mass to the amount of propellant needed for propulsive capture. It's only really worth it for missions to Uranus or Neptune or Titan orbit, it's borderline for missions to Mars, and counterproductive for missions to Jupiter, Saturn, or Venus.
  9. Mouse over it in map view. The maneuver has to be deselected (not have the colored handles showing).
  10. Yep, the turbojets have a significantly higher TWR than the rapiers off the pad, and they're not too bad at the higher speeds either. I also tried with a poodle upper stage, but it needed higher TWR to counteract the still-significant atmospheric drag.
  11. Aerospikes are the only engines with a nonzero Isp at 0 altitude on Jool. They have an Isp of 65 s there. That means their thrust is about 80 kN, so they can barely carry a small tank of fuel by themselves. I tried making a 900-part aerospike asparagus ship, but only got to about 5 km altitude on Jool. It's way harder than it was pre-1.0. Maybe the challenge should be how low can you go inside Jool's atmosphere and still make it back into orbit.
  12. Here's mine, updated some numbers for 1.0.2: And a more simplified version: An important disclaimer is that ascent delta-v varies significantly based on the size and shape of your rocket. Edit: changed maps to provide a range
  13. Here's one with 50.23% payload fraction (58650/116770), 8 rapiers and 4 turbojets on the first stage, 1 skipper on the second stage:
  14. Yeah, in fact as you get closer to the Sun below ~1,000,000 km the efficiency of solar panels actually goes down.
  15. The Skipper doesn't actually activate until all the aerospike stacks are depleted. There aren't any fuel lines on the ship. Here's a video: