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Armchair Rocket Scientist

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About Armchair Rocket Scientist

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  1. This all makes sense - I figured the mass of associated equipment would be approximated by the case mass and/or the density used for the part. However, the results I'm getting don't seem consistent with it just using the area density and canopy area. As an experiment, I edited ParachuteMaterials.cfg to reduce the area density of all materials by a factor of 100, then made a RealChute with an extremely small size, and a ridiculously small parachute with a 3 meter diameter. The parachute mass should be negligible - which was confirmed by the part mass hardly changing at all with changing ch
  2. How is the parachute mass calculated? My chute masses don't seem realistic. I am using RealChute, FAR, and Realism Overhaul, and attempting to make an Orion-like spacecraft. According to various NASA articles, each of the Orion's three main parachutes weighs about 300 lb (136 kg), is 116 ft (35 m) in diameter, and slows the approximately 9 ton capsule down to around 20 mph (9 m/s). However, testing with a 35m diameter nylon RealChute, using the Radial RealChute at the default size, with an approximately 3 ton spacecraft, the part mass was approximately 0.43 tons. Its performance was close
  3. Is there a way to use Realism Overhaul for realistic solar panels, electricity consumption, and so on, but without rescaling parts like command pods to human-size, and using the Stockalike RF engine configs? I'm working on an install with roughly 10x upscaled planets, and I want all the physics and part performance to be as realistic as possible, but keeping the multiples-of-1.25m scale factor, as appropriate for meter-tall Kerbals. I know the answer is probably somewhere in the configs, but I wanted to confirm that deleting the Engine_Configs folder that comes with RO and replacing it wi
  4. [quote name='wumpus']Just how many pound draw do you need to fire an arrow at orbital velocity? You aren't going to hit the Earth from ISS with any bow pulled by mortal man (ignoring slow, slow air resistance).[/QUOTE] No amount of draw. As you make the bow larger, it gets heavier, and the body and string of the bow have significant inertia. Ultimately, for a given bow design the speed will be limited by material strength and density. Maybe with some extremely complex design you could get an arrow to go supersonic, but orbital velocity is comparable to the detonation speed of high ex
  5. [quote name='Cirocco']I made a thread about this in the space lounge as well and I'll repeat the same arguments here: this landing has almost nothing in common with what SpaceX is trying to do. The falcon 9 is designed to boost a payload + upper stage halfway to orbit. It's far, far, FAR bigger, heavier, more flexible, its engines don't allow it to hover like the New Shepard, etc. SpaceX has to overcome a whole lot more difficult problems. That being said, this [I]was[/I] a historic event: it was the first rocket that passed the Karman (I swear I almost typed Kerman there) lin
  6. The simplest answer: you can't simply "deal with" this problem because it's part of physics. If a vehicle is aerodynamically stable flying nose-first, then it will be travelling nose-first when the parachute deploys, and subsequently have to "flip" around. There are only two ways to "fix" this. 1. Deploy the parachute from somewhere other than the nose, resulting in an "on-its-side" descent attitude. This is similar to the "rogallo wing" concepts for Gemini, as well as ballistic chutes for airplanes. For a capsule, you're lying on your back in normal flight, so with the capsule
  7. [quote name='SomeGuy12']If you wanted to dock to a rotating station along the rim, cuz you're crazy...can it be done? Let's see...if you draw an imaginary line out in space representing a tangent coming off the rim, and then position your spacecraft along that line, I think it would become an intercept problem. Suppose there's a particular docking port that passes a point on the tangent line with every revolution. You want to match velocities with the rim speed, and then arrive at the intersect point between the tangent line, the station, and the docking port at exactly the
  8. Depends on how much payload and how much time. A major constraint on a mission like this is that the power output of RTGs gradually declines: making a probe that gets to Sedna 50 years after launch isn't necessarily that useful. How big is your course correction? Your probe is going to be going FAST when it flies by Quaoar if you want to reach Sedna in a reasonable timeframe. Even a tiny change in direction could end up costing multiple km/s of dV (which is a big deal for a small probe). Now, I have a question of my own: Why Sedna? We've already done a flyby of Pluto, so we have a decent idea
  9. https://en.wikipedia.org/wiki/1997_Pacific_hurricane_season https://en.wikipedia.org/wiki/1997_Atlantic_hurricane_season
  10. Environmentally a terrible idea, and according to the wikipedia page it would have required "six new nuclear power plants" to pump the water over the Rockies. Desalinization plants would likely be cheaper and more environmentally friendly, especially since much of the infrastructure could be built in desert areas.
  11. I don't think 57 solar masses is enough to exceed the Eddington limit, since there are stars over 100 solar masses.
  12. How do you know it isn't behind us? Say, that the probability of a species developing to the point where it's capable of forming a technological civilization is extremely low, and very few planets have agriculture, much less Dyson Spheres.
  13. There are plenty of altimeters designed for amateur rockets that will read up to 100,000 feet with barometric sensors. Note: Don't use these on a balloon. They have high sampling rates (meaning they probably won't record hours of flight) and use accelerometers to detect a launch: the gentle ascent of a balloon probably wouldn't do much. You should be able to find Arduino-compatible pressure sensors with that resolution. I'd also advise asking this question on DIYDrones or another amateur weather balloon forum: they'll be much more able to help you than this forum.
  14. There are several problems. 1. Your grid must be separated from the floor by at least a few millimeters, be strong enough to support the weight of people and furniture, and be fine enough to not be unpleasant to walk on. Does this even exist? 2. You still have to clean the grid itself. Using GMO organisms for more efficient disposal of trash is a decent idea, but it's better to just use a composting vat. If you want an environmentally way of cleaning off objects, don't bother with a whole slime mold in your house: farm the desired microorganisms for their digestive enzymes and use the enzymes
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