Nibb31

It's an annoying trend in "hard science" circles to look down on humanities and social science as if they were somehow inferior. That's just ignorant. Economics itself is not a doctrine. It's the study of economical systems. Those systems, whether you agree with them or not, exist, affect our lives, and deserve studying. There are economical predictions that stand and there are also laws of economics. What is unique in economics, is that it studies a field that is totally artificial. Money, value, and wealth are man-made concepts, yet they follow their own laws and phenomena that we can hardly control. I find that fascinating. History is also a social science. You can't really use it to predict an outcome, but would you really argue that historians are not proper researchers ?

Many of those problems are currently alleviated through medication and or exercice. This currently allows long duration stays, without artificial gravity. Long-term studies on the ISS allow medical teams to improve those treatments on a regular basis. There is no reason that we couldn't envision 2 or 3 year missions in the near future based on those findings. On the other hand, rotating rings might have negative effects due to the Coriolis force that is imparted on the inner ear and other body fluids. We simply don't know if those drawbacks exceed any potential benefits, and there will need to be many years of research before that question can be answered. What we do know, however, is that building a rotating ring in space is excessively complex and expensive. If we really needed a centrifuge, which again, is not a certainty, there are much easier ways: either rotate the entire spacecraft or attach modules on a tether.

Because it takes 3 days for any projectile launched from the Moon to reach a target on Earth. And that's after waiting weeks for the proper launch window to hit that target. The projectile would be spotted right away and 3 days is enough to have your own country wiped out. It's also enough for your enemy to prepare to shoot down the projectile in the upper atmosphere. It would also take a massive amount of resources to build a military facility on the Moon. It took a Saturn V to put a 15 ton lander on the lunar surface. Sending a 50 ton missile to the Moon only to launch it back to the Earth would be a massive waste of resources. You'd be better off putting it in orbit, if that wasn't equally stupid.

That schedule is way too optimistic. SpaceX has yet to recover a booster. After that, it will be a while before they get to a stage where they are confident enough to reuse it. They will need to tear down the first couple of recovered stages, x-ray the parts, check everything, and rebuild and test them. They will also need to find a customer who is actually willing to risk their payload on a reused stage. NASA won't, and I don't think DoD will either. That kind of limits the point of reusability. And again, Falcon XX will only be built if there are customers willing to fly their birds on it. There are no payloads for it and customers aren't really queuing up with 100 ton payloads on the launch market.

It's a social science, so yes. But it's an interesting subject. On one hand, economical phenomena are real, measurable, and complex. On the other hand, the economy is a completely artificial area where all the interactions were voluntarily engineered by Humanity. All other sciences strive to understand and describe nature, whereas economics tries to understand an man-made construct that we could simply tear down and replace if we wanted to.

There are no "Soviets" any more. The country is called the Russian Federation and the current ruling party United Russia is considered conservative and nationalistic. By most standards, it's closer to a patriotic authoritarian right-wing party than to communism or socialism. Its main opposition is the Communist Party, which is in the minority. Constantly referring to modern Russia as the USSR is like calling modern Germany the IIIrd Reich, or Italy the Roman Empire for that matter. It's anachronistic and inaccurate.

He might be authoritarian dictator, but that doesn't make Russia a Soviet country. Learn the difference.

I don't think anyone is seriously thinking about sending one to LKO ;-) Nobody is advocating using it to go to the ISS. That requirement was removed years ago and won't be needed because the CCDev program is on track. If congress wants to send men to Mars, then they'd better start allocating a budget. It would take at least 10 years to develop the technology and another 10 years to develop the vehicles to go there, and that's if they started allocated funds right now, which they aren't. SLS can't sit around for 20 years waiting for a payload, and any interim mission hardware requires even more funds, which only pushes Mars back another 10 years. It is an overly specialized launcher. It's specialized in 60 to 130 ton payloads which don't exist. You don't get more overly specialized than that really.

Current science doesn't consider any possibility of Venusian life.

The Falcon XX is run by a private organisation with no budget either. It's a paper rocket. You only build a rocket, especially a big one like that, if you have customers. There are zero customers for a super heavy lift rocket.

http://en.wikipedia.org/wiki/Chinese_exclusion_policy_of_NASA

Congress won't come up with a huge magical budget for NASA the moment SLS comes online. That's not how things work. Besides, the infrastructure budget for SLS will keep NASA bogged down. First of all, aerospace projects rarely take less than a decade to be developed. That means that if Congress suddenly approves Skylab II or DSH or a Mars mission in 2017, it won't fly before 2027, meaning that SLS will be sitting around gathering dust during all that time. In fact it won't, because Congress won't allow the infrastructure expense and will cancel it well before any payloads are ready.

Unlike the Apollo LM, the LK lander used the Block D for most of its descent before staging at the last minute. It only used its own engines for the final descent. On ascent, all it left on the ground was a metal frame with the legs, the ladder, and a couple of auxiliary tanks. The big central nozzle is the main engine. The two medium sized ones are the backup engines. The four smaller ones are exhaust nozzles. On ignition, both the main and backup engines would start up. Then the backup engines would shut down if the main was running properly.

An operational space-suit is either for flight or EVA or training. The color of a flight suit should be bright orange or day-glo yellow to increase visibility in case of a bailout. The color of an EVA suit should be white for thermal reflection. The color and material of a training or test suit should replicate the operational flight or EVA suit as closely as possible. Black/dark grey with battery-powered leds for "ground-based testing" (whatever that is) is just silly PR that serves no functional purpose.

Interestingly, the Soviet LK lander had two sets of ascent engines for redundancy, just in case. They didn't want to strand their cosmonaut on the Moon either.

"only" two crews is 12 people too many. We been through this discussion dozens of times already. SLS is on budget and on schedule, but it will have a similar fixed infrastructure cost as the Shuttle (the only real savings will be the recovery ships and SCAs). Currently, only the two test flights EM-1 in 2017 and EM-2 in 2021 are manifested. After that, NASA plans on a maximum flight rate of one launch per year. Only two Orion service modules have been ordered from ESA. There are no missions for the SLS, no payloads, and no money to develop any until SLS is operational. It takes time to develop payloads and mission modules, which means that there will be a gap of several years between EM-2 and any future missions. It is unlikely that it will survive that gap.

The LM ascent engine was the only part of the Apollo mission which had no redundancy and no survivable abort. It was the single most critical part, which is why it was designed to be as simple as possible, using hypergolics and very few moving parts. The engine cover was even removable so that the astronauts could tinker and bang on it if a valve got stuck. AFAIK, it worked flawlessly each time.

Duplicate thread: http://forum.kerbalspaceprogram.com/threads/73741-Vote-on-NASA-s-New-Spacesuit

The whole assembled ring thing is a silly idea. You'd be better off with a giant inflatable or just rotate the entire spacecraft. For all we know, artificial gravity isn't even necessary. You'd just be adding lots of complexity for very little gain.

In the real world, nobody uses the term "pod". It's either a capsule, or a module, or a spacecraft. If it's going to be on looks, then DreamChaser wins... or Kliper.

The cost was mainly due to the fixed cost of maintaining KSC, JSC, the VAB, two launch pads, two recovery ships, two 747 SCAs, three MLPs, and a standing army of technicians and engineers to run, maintain, repair, clean all that infrastructure. Then you need the administration folks to train, manage, feed, house, and support that standing army and to procure supplies and parts for all that machinery. The most obvious way to cut the cost of the STS was to launch more often in order to share those fixed costs. SLS will have very similar fixed costs, but for only 1 launch per year, which is going to be even more problematic.

Same thing. Use a star tracker and inertial measurement. Ground control can confirm position from trajectory calculations and measure the time it takes to get a message back from the spacecraft to know how far away it is.

Since the ISS is controlled from Houston, it would be hard for the USSR to confiscate it.

There isn't anything to handle because SOIs don't really exist. The IMU could be switch to various referentials depending on the mission phase. A fun tidbit is that there were red circles on FDAI (the real name for the nav ball) which corresponded to the "normal" and "antinormal" position. The astronauts had to make sure to never point the spacecraft in those directions because the IMU (inertial measurment unit) gimballs would lock up which would cause them to lose attitude reference information for the rest of the mission.

You're wrong by at least one degree of magnitude. The global production of nuclear waste is 20 000 tons per year. That's actually a lot of stuff to haul around safely. Although live fuel and reactors are protected by thick concrete structures, spent fuel is usually stored on-site in pools that are only covered by lightweight hangar structures until it cools down enough to be carried away. Fukushima showed that this kind of waste storage is inadequate, because it relies on the integrity of the pool and the pumps to keep the water cool. If spent fuel gets left in the open air, there is a very real risk of radioactive fire, which would be hard to put out.