RCgothic

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Everything posted by RCgothic

  1. Actually, NASA doesn't know why *some people* experience taste differently in space. Some don't notice a difference at all, and afaik there's no supposed biological mechanism that would make food taste different in the long term (stuffy "space head" doesn't tend to last that long). It could just be that foods have been prepackaged for a long time before consumption. Or it could be that food scents just have to compete in an extremely odorous environment, and a larger living area with better air conditioning would solve the problem. We haven't ruled out all the non-biological factors, basically.
  2. Equal compensation for equal service
  3. I suppose this means that SpaceX will simply bid more in future.
  4. If the goal is to send Orion *and* a capable lander to the surface of the moon, then as tater said the baseline is 76t to TLI in a single launch. Can any version of SLS do that? No. Block 1b can comanifest 10t to the moon with Orion. If you use that as additional propellant, that gets you only to LLO. It's not enough to accomplish a mission. Block 2 can comanifest 19t with Orion. *Maybe* that gets Orion into LLO with a minimal lander. Except that's not planned. The only architecture which makes any sense using SLS and Orion is to put Orion in LEO using a different booster (falcon heavy can lift the mass, 2/3 reusable, possible form issues), and mate it to a large cargo on an EUS for TLI. The bigger the cargo the better. SLS block 2.
  5. And not only because of the better architectures a larger rocket enables, but because constantly having to prove all new stages, as well as retooling VAB bays, MLPs and Pad 39B for different rockets, is completely stupid. Block 2, all up, go! Maybe the rocket explodes. Maybe bits fall off à la Apollo 6. But then you fix it.
  6. Yellow is frequently lifting or handling equipment, I think that's pretty common across industries.
  7. Well I feel sheepish. I must have been overcomplicating my search terms.
  8. What are Soyuz's exact numbers? I've struggled to find them in my own searches.
  9. F9 B5 has now had 19 successes from 19 missions. The success rate based on Bayesian statistics is: P{S} = (n{S}+1)/(n+2) Where: P{S}= Probability of mission success n{S}= Number of successes n = Number of attempts P{S}= 95.2% For falcon 9 as a whole, it's 76 successes from 78, or 96.3% That has to be close to an industry leader surely.
  10. It's not the composition (identical), it's the behaviour. If you've seen the scene in "Passengers" where the gravity turns off and the effect that had on the swimming pool you'll have some idea. Water in zero g is sticky. It forms balls. It clings to things and covers surfaces. There's no buoyancy, so you can't escape by letting yourself float. Which way is out? Then when you do get to the surface it clings and distends around you, refusing to let you go. Found an external handhold to pull yourself out? It'll cling to that too and come with you. It's far too difficult to get out of. In zero g large quantities of water is an extreme drowning hazard. The moon has gravity so it would be far less hazardous to have your swimming pool there.
  11. Pretty sure that much free water in zero gravity would be an extreme hazard. At least some gravity/spin is required at a minimum. Plus it's heavy, a tonne per m3. It's not something you want to be carrying around on a spacecraft unless it serves dual purpose. That said, I've heard that if you had a swimming pool on the moon, humans would be able to leap like dolphins. If you were using hydrolox as power, then that's worth taking to the moon for that alone. You could then condense the products and make use of the water byproduct to create the solar system's best water park!
  12. I wonder if red components are a colour code for "not for flight", e.g. supports or blanking plugs that need to be removed before the rocket reaches the pad.
  13. Twice the money, eight times as many first stages. I guess the relationship of space expenditure to rockets is cubic.
  14. They claim 98% efficiency and an exhaust imparted with so much energy it burns blue. But the only available stats are from their own promotional materials and it hasn't had a full-scale test - yet. 365s is 6s better than the best available vacuum engine right now. I can *just* believe that there's 6s to be had out of a monolithic 3D printed combustion chamber, but wow even so.
  15. Sounds like it could be possible damage caused by rough seas yesterday. Seas are calm today, so that's not the reason.
  16. Interestingly, 15,400kg to LEO is over 90% of Falcon 9 FT's nominal payload to LEO (reusable) according to Wikipedia. I remember people saying payload to LEO is a nominal value for comparison that could never actually be used, and that the payload adaptors can't handle it. Wikipedia actually lists the F9 B5 PFA structural limit as less than 11te! I guess payload to LEO isn't so nominal anymore.
  17. According to Reddit, May's launch was 227kg per sat, ~13,670kg total. On this launch it's up to 260kg per sat, 15,400kg total. So the sats are indeed heavier. It may be as sh1pman says, material changes due to burn-up concerns, or they may simply be more capable. May's launch was v0.9 prototypes, whereas this is officially the Starlink-1 mission.
  18. It's been said again and again. SLS/Orion isn't the rocket/spacecraft combo we need. For LEO assembly it's too expensive, flies too infrequently, and has nowhere near enough dwell time with a hydrolox upper stage. For BEO operations it doesn't have enough throw weight to accomplish anything meaningful in a single mission. Which brings us straight back to too expensive, flies too infrequently, and has nowhere near enough dwell time, because the lack of throw weight makes rendezvous a necessary mission requirement. You don't need a big man-rated (and therefore expensive) booster for getting a crew to orbit anymore. Rendezvous is a solved problem. Ares absolutely had the right idea (minus the bonkers srb design). You want a big dumb booster that's payload agnostic, inexpensive, and can fly frequently. 200t to orbit. Then you'd have a range of things you could stick on top of it to suit the mission. It doesn't have to be fancy, or have great BEO performance. That much is handled by the payload. It just needs to get to LEO as cheaply and as often as possible.
  19. Planes accessed by steps from the tarmac often load front and rear as well. Note the twin boarding steps in this photo.
  20. As an experienced flyer and engineer not prone to being unsettled by turbulence, sitting where you can see the wings flexing probably wouldn't be helpful. In severe turbulence that's what gets me the most. I'd suggest an aisle seat in the nose, well forward of the wings.
  21. Ok, I'll bite, using my best Googlefu and an estimate for head length: The average human is 67kg. Average height 1.67m. The cylinder is 1.52m radius. Let's break the body down into 3 regions of roughly uniform mass distribution. Legs are approximately 35% of body mass (21.7kg) and are on average 45% of total height (0.75m). Their average radial position is 1.15m. They contribute 24.9w2 to force. Head and neck is roughly 8% of body weight (5kg). They're about 30cm long. That puts the average radial position bang on the spacecraft axis. It contributes nothing. Trunk and arms is the remainder. 35.3kg and 62cm long. The average radial position is 0.46m from the axis. They contribute 16.4w2 to force. The total force due to centripetal acceleration is therefore 41.3w2. 1g on 67kg is 657N = 41.3w2 15.9 = w2 w = 4 radians per second = 94rpm. Incidentally your toes would be experiencing approx 2.47g.