zolotiyeruki

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About zolotiyeruki

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  1. zolotiyeruki

    SpaceX Discussion Thread

    I wonder who's gonna be the first Youtuber to do that and post a video. Scott Manley? Hazard-ish? Mark Thrimm?
  2. zolotiyeruki

    Biggest Plane with a Juno

    Looks good! You've been added to the leaderboard
  3. zolotiyeruki

    SpaceX Discussion Thread

    The only way an LNG freighter turns into a FAE is if 1) it stays there a long time, 2) the LNG just sits there and boils off, and 3) there's no wind for that same period of time.
  4. zolotiyeruki

    SpaceX Discussion Thread

    Thanks for clearing up my misconceptions. Could an inflatable donut-shaped heat shield slow it down enough before it hits the denser atmosphere and the accompanying dynamic pressure?
  5. zolotiyeruki

    SpaceX Discussion Thread

    Is the re-entry heating worse than what the engine experiences during ascent/orbital insertion? It makes sense to have the second stage enter engine-end-first. That way the acceleration due to drag will force all the fuel down towards the engines, just like it is during ascent. No need for ullage motors. Another question: does it need to re-enter at 7km/s? Why not do a big retro burn? Let's do the math. The empty mass of the 2nd stage is 3.9 tons, and it carries about 92.5 tons of fuel. Let's say it keeps the last 10% of its fuel*, and has a mass of 13 tons. Assuming an Isp of 300, that means it could slow down from 7km/s down to 3.5km/s before hitting the atmosphere. Is that slow enough that the engine wouldn't need extra protection against the heat? * yes, I know that this would impact the payload capacity to orbit, but a lot of payloads are well under the 22.8 tons capacity anyway
  6. zolotiyeruki

    Biggest Plane with a Juno

    That's a nice-looking plane, but I'm afraid I can't afford to bend the rules. Any chance you could rebuild it with normal-sized pylons or other structural members?
  7. Here's my STS-2T mission. I ran into one major problem due to the design of this iteration of the craft--even after the boosters are separated, it is *very* heavy (lots and lots of LF). Since LV-Ns burn fuel relatively slowly, that meant I was very heavy on re-entry, and I somehow also ended up several kilometers south of KSC. Overweight, and very little thrust, it was a desperate struggle to get the shuttle back to the KSC. But they made it. https://imgur.com/a/8ubIAZB
  8. zolotiyeruki

    Redirect asteroid by mining it for reaction mass?

    I think Krakatoa's effects were due to the vast amount of ash spewed into the atmosphere, rather than the raw energy released. Tsar Bomba would be 1/2000th of the hypothetical asteroid.
  9. zolotiyeruki

    SpaceX Discussion Thread

    Soyuz uses rockets at touchdown, doesn't it?
  10. zolotiyeruki

    Redirect asteroid by mining it for reaction mass?

    Well, let's run the numbers. Let's take a 1km spherical asteroid, and assume a density of 5,000 kg/m3. The chelyabinsk meteor came in at about 19km/s. That gives us enough to calculate the kinetic energy. Mass of asteroid: 5,000 * 5.23x10^8 m3 =2.62 x 10^12 kg Kinetic Energy of 1km asteroid: E = 0.5 *mV^2 = 0.5 * 2.62 x 10^12 x (1.9x10^4)^2 = 4.73 x 10^20 J By comparison, a one-megaton nuclear bomb releases about 4.18x10^15J, so this asteroid has about 100,000 times as much energy. The sun imparts 174 petawatts (10^15) on the earth, so about 45 minutes of sunlight is equal to the energy of the asteroid. I could be wrong on this next part, but if you assume that the asteroid entirely burns up in the atmosphere (i.e. no surface impact), it wouldn't have a long-term impact on the climate. The earth would heat up slightly, start radiating more heat into space, and over a few months all that energy would get dissipated. Of course, an asteroid that hits the atmosphere at such an exact re-entry angle and burns up without exploding is hypothetical--at that speed, by the time it would have vaporized, it would have long since exited the atmosphere.
  11. zolotiyeruki

    SpaceX Discussion Thread

    I suppose there is some precedent...
  12. This is one of those "please tell me what I'm missing, and how I'm horribly wrong and/or stupid for even coming up with this" questions Could you take a NERVA plus some mining equipment, and use an asteroid's mass for reaction mass? NERVAs are usually expected to run off hydrogen for efficiency, but you'd need to heft a whole lot of hydrogen to redirect a very large asteroid. What if instead, you fed the nuclear reactor ground-up asteroid as a propellant? Off the top of my head, I can think of a few issues, like "how to feed a solid into an engine", and making sure you don't melt the engine itself when vaporizing the asteroid dust. But those seem like solvable issues. Or, as an alternative, could you use some other sort of mass driver (catapult of some sort?) to hurl chunks of the asteroid away, gradually changing its path with each launch?
  13. zolotiyeruki

    SpaceX Discussion Thread

    The sound of the cold gas thrusters might ruin the experience, though...
  14. Thank you very much! Yeah, landing the orbiter wasn't much of a problem. I did open the cargo bay doors on purpose, actually. When I detached from the carrier aircraft, I was quite close to the KSC, so I dove pretty aggressively towards the runway. The open doors ensured that I could still hit the runway at a reasonable speed after diving from 5km. STS-2T should be interesting--the orbiter carries a LOT of fuel after achieving LKO, and burning that much LF with only LV-Ns before landing might be a bit challenging. Of course, by now I have several iterations of my shuttle design to choose from...
  15. Here's my STS-1T. Had to mess around with the CoL/CoG on the carrier aircraft by trial and error 'til I got it right, since I couldn't test it in isolation. https://imgur.com/a/QBOLGmT