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About peadar1987

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    Senior Rocket Scientist

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  1. Yup, they'd hear the booms alright. As to whether it would damage the planes or not, I would say no, my gut says the force from a sonic boom at that range would be less than the forces the aircraft is designed to withstand in normal operation. Although I think then wake turbulence could become an issue for both aircraft after passing each other
  2. When calculating the ISp though, you need to take into account the escape velocity of the earth. Any reaction mass you throw out is going to Newton's Third Law you back to rest unless it's expelled from the system. The escape velocity from the earth's surface is about 11,000 m/s, which means your exhaust velocity has to be at least this high to get any net thrust at all. Effectively, 1100s is going to be subtracted from your ISp straight off. This means that the only choice is really ion thrusters. Of course, this penalty will decrease as the earth's gravity does, because we're decreasing the earth's mass significantly, so we're going to get a nice integral function to solve, and the final dV is going to be hugely dependent on what ISp we start with.
  3. Well in theory we can just build arbitrarily large structures in space. If we have eleventy billion Soyuzes, we can take 5-10 years to develop a way of reliably coupling fuel tanks together like in KSP, and put anything on a transfer trajectory to anywhere. And if it blows up because it's too complicated or too untested, we just build another one, because we have eleventy billion Soyuzes. With all of the world's military budgets combined, that's about $1.7 trillion a year. That would easily pay for a permanent Mars colony (This article estimates a Mars program with 9 trips, like Apollo, would cost $1.5 trillion over the project lifetime, which given launch windows would likely be 20-ish years). With current technology, we could land people on Mars, that's just a question of Delta-V. And we wouldn't need to perfect closed-loop life support either, as sending fresh supplies is also just Delta-V as well. For $1.7 trillion a year we could just keep sending stuff out whenever the colonists looked like they might need it. Not an elegant solution, but with that sort of budget it doesn't need to be.
  4. Ah now, there's still plenty of great moments in spaceflight. Cassini... Rosetta... New Horizons... Curiosity... I wasn't around for the golden era of manned spaceflight, but there's still a load of incredibly cool and engaging unmanned stuff going on, even if the ISS isn't your cup of tea.
  5. I'm on an old version of KSP, but my MM patch a few posts up should still work.
  6. And when I was about three years younger than I am now, NASA was going to recover an asteroid to study. Boo lack of funding!
  7. Yes, but on the contrary, MOAR BOOSTERS!
  8. If you want to be really clever you just put two turrets with a half-hemisphere field of fire back-to-back. Same coverage, far less complexity.
  9. Just a guess, but if it was formed from remnants of Theia and ejecta from earth, the individual pieces would all have been on either hyperbolic or suborbital trajectories, but when they smashed together, they would change each others' paths into something that didn't hit the surface or escape the system. Then once you have an elliptical orbit in a "dirty" region of space, it will tend to circularise, as the body is hitting things harder and more often at perigee when it is moving faster. As well as circularisation due to tidal effects.
  10. I was just going to say he's probably a lot further away than the looks due to foreshortening, but I like this idea better
  11. And what type of energy are you trying to deliver to it? Kinetic? Thermal? Potential? Does it matter if the object is destroyed in the process? What is its mass? What material is it made of? Are you working to a tight timescale, or have you got as long as you need?
  12. Hammer?! Although i you want to game the question, the easiest way would be to move it to somewhere warmer than it is now and leave it there for a while.
  13. Of course. But I'm not arguing that the Shuttle is terrible, or that it is better or worse than any other spacecraft, I'm just disagreeing with Yobobhi's claim that "the Commies were bad at engineering".
  14. Cost is a pretty big handicap. If I want to put a 1000kg payload in orbit, cost and reliability are the two things I'm going to use to decide which launcher is "best". Which is why the Soyuz is the "best" launcher for a lot of the applications we've had for the past 30 years, and is still flying whereas the Shuttle has been retired, in spite of its superior technical capabilities in certain areas. All engineers are given a budget. If you meet the design brief within the budget then you're a good engineer. Bigger budgets don't make better engineers.
  15. You're completely missing the point. The 747 is better than the Shuttle at what it was designed to do. The Shuttle is better than the 747 at what it was designed to do. Heck, my lawnmower is better than the shuttle at what it was designed to do. Just using total up-mass per launch as the be-all and end-all of launcher comparison is far too simplistic. The Apollo LEM descent stage could put a payload of 4,700kg on the Moon. The Shuttle could put zero payload on the moon. Does this mean that the LEM was categorically a better spacecraft, or simply that it was designed for a different purpose?