Jump to content

Lukaszenko

Members
  • Posts

    356
  • Joined

  • Last visited

Everything posted by Lukaszenko

  1. "Re-using space vehicles will help slow the proliferation of debris, which has become a substantial risk to space exploration." Uhhh...that's their understanding of why they're trying to reuse rockets?
  2. Is there a relativistic equivalent of the Oberth effect? Oberth makes your rocket more effective due to classical physics equations. When approaching C, surely the efficiency rises even faster than can be explained by Oberth...
  3. So let's examine this. What would happen if Coca Cola claimed that they are better than General Motors because they were the first to make Sprite? You wouldn’t want to jump in and call foul? Because that’s exactly what happened here, and why this discussion is even taking place. Nobody was saying one is better than the other until BO themselves tried to say it. So it’s not a question of fanboism, it’s a question of A trying to make themselves look better at the expense of B, despite half-assing whatever it was that B was doing. BO basically jumped out of the sidelines in front of a marathon runner, and started celebrating that they crossed the finish line first. Even if I hate the marathon runner, I’ll probably still come to his defense. And probably so would you. And why do I need rocket building credentials to see that an orbital launch system is more impressive than a suborbital one? You’re seriously claiming they are on the same level?
  4. Yes, they were first at flying the Wright Flyer. But the fact that they were working on the Wright Flyer at the same time as SpaceX was working on the Concorde, and flew it only a couple months before the Concorde, is precisely what makes their "first" so much less impressive.
  5. It keeps being brought up in these discussions that the Falcon 9 1st stage is suborbital, but I fail to see the relevance of this. Seriously…who cares? It is part of a system used to launch something into orbit. As such, it is not meant to nor will it ever work by itself. It’s like comparing a slingshot to an AK47...they’re both just about as effective by themselves. It’s only in combination with their bullets that their differences really start to show. The point is that the most expensive scrapped part of launching something into orbit, is being recovered (and eventually reused). Whether this part itself goes into orbit, to the moon and back, leaves the atmosphere, or never even so much as leaves the ground is a red herring.
  6. I don't think whether it's an actual mission or a test is all that relevant here. What is relevant, is that one rocket puts a payload in orbit, and the other doesn't. That difference is so huge that it's quite literally astronomical. Once you're in orbit, you're half-way to anywhere. But, you have to get to orbit. Not close, not almost there, not even 99% there, because anything less than a stable orbit, and you're coming back. And New Shepherd is nowhere near significantly close to orbit to be even worth discussing. Yet.
  7. It can't be that impossible where I would say "never". If we can have video from almost directly below a rocket launch, or even from the inside of a Tokamak, I'm sure we can have one of a rocket landing. For that matter, why do we even need radio waves?
  8. Everybody else keep seating on edge when watching these things, thinking that this time it will blow up for sure? And then every small spark, flame, smoke, detail means "yup, it's gone...damn." I still like watching airplanes taking off/ landing, but it just doesn't have the edge-of-your-seat excitement of a SpaceX rocket launch. I wonder if the risk is half the reason, especially since I can't help thinking that so much is riding on a SpaceX rocket (beside the actual payload).
  9. ...so it looks like they bring the periapsis even lower than zero. Not surprised, I didn't expect a direct translation from the Kerbal world here.
  10. Basically when the rocket exceeds the exhaust's velocity, the rocket gains MORE energy than the total chemical energy in the propellant. The efficiency goes past 100%.
  11. I don't understand, is the webcast starting in 1 minute or is the rocket already taking off??
  12. What does that mean "payload to Pluto"? As in, land on Pluto? Send there on a Hohmann? By way of 40 gravity assists? Because New Horizons did none of those, and I think when we're talking differences of decades (or even centuries?) they need to be a bit more specific.
  13. You're saying that "theoretical ... yes" there is a maximum, or "theoretical ... yes" you can raise ISP without bound? I understand that the exhaust will never reach the speed of light...it will just start to gain more and more mass at some point as you pump more and more energy into it. But that would still continue to increase the ISP, no?
  14. Might be a bit off topic, but is there a theoretical maximum ISP you can get from a rocket engine? Can you, for example, just keep pumping more and more energy into the ions of an ion engine, raising their exhaust velocity and ISP without bound?
  15. I can't understand why acceleration is not taken into account when calculating the greatest stress on a vessel. A rocket accelerating at 100 gs in vacuum will be experiencing more stress than one going Mach 3 through thin atmosphere, I imagine.
  16. I can understand that the sun moves differently. Perhaps it's higher in the sky and perhaps you have to turn a different direction if you were following it. But I'm curious how this all plays out in real life. I mean, firstly, the sun moves slowly, and hardly anybody ever pays attention to how exactly it moves. Are the effects of your position on the earth enough to make you suddenly realize, or think that "holy ish, the sun is moving the other way!"?
  17. So a colleague came back from Australia (I live in Netherlands), and after my obligatory "does the water flush the other way?" joke, he said that while he didn't pay attention, he did notice that "the sun moves the other way". He insisted that he means "west to east". At first I dismissed him as crazy, but depending on who I ask they say that indeed the sun should appear to move the other way....or at least move in such a way that it seems like it's moving the other way. Or something...I don't even know. But the question is, is there any way to make sense out of the comment that in Australia, the sun moves "the other way"? I welcome discussion, but personal experience would also be nice.
  18. It does not, it only has to throw away photons. A flashlight can be a photon rocket, for example.
  19. As was mentioned, most of the energy goes into moving the exhaust (which is moving FAST) as opposed to the actual spacecraft. Since energy is exponentially related to speed, to throw the exhaust out the back 2x fast takes 4x as much energy, and yet your spacecraft only accelerates 2x faster. And if you think that's inefficient, take a look at a photonic rocket: 300 MW per Newton of thrust.
  20. I don't care what anybody says, I like the hosted webcast. Much more dramatic. I don't think this will ever get boring. Routine maybe...hopefully, but not boring. I could sit at the airport and watch airplanes taking off and landing all day.
  21. Which is exactly how much pressure is at the bottom of the rocket, which is how hard you have to shove the fuel to get it in there. Same difference, no?
  22. Is there any difference between pumping "uphill" and pumping to the bottom, but against the pressure of the "hill"?
  23. I also played an earlier version in Ironman mode, and I concur that it gives you more enjoyment from the game. Makes you be VERY careful about how (or if) you aerobrake and how much extra fuel you bring, makes you more meticulous when it comes to testing, especially manned, and gives you reason to build in escape systems....all just like in real space programs. Lately though there was too much dancing around with all the shifting variables in the game, so I reverted to quicksave/ load mode. Even in Ironman though I recommend saving often, in the very likely case that you lose the mission because of a bug.
  24. It's also empty, with all the heavy bits at the bottom. The middle just has to support its own weight. I doubt that it can do this trick fully loaded.
×
×
  • Create New...