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Visiting Our Red Space Neighbor
Enthusiasm for visiting our red space neighbor seems to be growing. m4dm4n writes "A study carried out by MIT's Aeronautics and Astronautics department has concluded that getting men to Mars in the 2020 timeframe is possible. The intelligent re-use of crew habitat modules, propulsion stages, and engines in various missions will enable NASA to significantly reduce their initial timeline which was well past 2030." Relatedly, ErikPeterson wrote to mention a Space.com article where Neil Armstrong says getting to Mars may be easier than getting to the Moon was back in the day, because of the hurdles they had to overcome. From the article: "It will be expensive, it will take a lot of energy and a complex spacecraft. But I suspect that even though the various questions are difficult and many, they are not as difficult and many as those we faced when we started the Apollo (space program) in 1961." We're starting to understand more about the red planet as well, as madstork2000 writes "The BBC is reporting on the possibility of active volcanoes on Mars. So now there is water, heat, and soon big business when 4Frontiers gets there. Hopefully we'll get a Google Mars soon to check it out up close."
Depends on where the Earth and Mars are in their orbits. Also depends on where Earth and Mars are in their daily rotations, as for a lot of the day your servers would be on the wrong side of the planets. You would need to set up a satellite relaying system, and a global radio network in order to be able to have constant communication. And even with that, there may even be times when the Sun is in the way, and communication doesn't really work. That is why some people propose using the Lagrange points as good places to put communications relays.
This is all actually important for if we ever want to actually send astronauts there.
According to Wikipedia, "Teflon is the brand name of a polymer compound discovered by Roy J. Plunkett (1910-1994) of DuPont in 1938 and introduced as a commercial product in 1946." As for Velcro, "The hook and loop fastener was invented in 1948 by Georges de Mestral, a Swiss engineer. The idea came to him after he took a close look at the seed pod burrs which kept sticking to his dog on their daily walk in the Alps."
That's a very interesting question, and you are right, it does often seem to b conveniently ignored. I did find a couple of rather woolly links here and here. There are of course many other links , but they seem largely preoccupied with managing food, oxygen and human waste rather than actually getting the astronauts back off the Martian surface.
Modest doubt is called the beacon of the wise. - William Shakespeare
Yes, Teflon came out of the Manhattan Project, specifically the gas uranium enrichment work at Oak Ridge, TN. Uranium Hexafluoride is nasty, nasty stuff, and Teflon was the only material they found they could make workable valve seals from.
"...Depending on Mars's distance from Earth, which can vary by as much as 200 million mi. (322 km), radio signals from the planet can take anywhere from 4 minutes to 21 minutes to reach Earth...."
YMMV I guess.
Modest doubt is called the beacon of the wise. - William Shakespeare
Google Earth Hacks has overlays of all the planets! So if you have Google Earth, you can have Google Mars!
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/., so I don't expect much rational thought, but:
>Considering that the government has severely increased spending (Iraq,
>Katrina) while decreasing money input (less taxes taken in), something
>is going to suffer.
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>Education is almost always at the front, and I'd say that NASA is second
>in line for the big axe.
This
Tax revenues have significantly increased since tax cuts were instituted. And, after shoveling increasingly large amounts of money at public schools for 50+ years, Johnny still can't read - in fact, education is worse than ever. One might be tempted to reach the conclusion that your underying concept of taxing people to get more money to improve education is simply wrong.
Total income at the federal level is up.
The tax cuts enabled economic growth, which put people to work which allowed.....more incomes to be taxed!
Tax cuts are actually, at certain taxation levels, a way to INCREASE net income. It has been made clear that the Bush tax cuts were made at this level.
They could do it now with the images on file from US, ESA, and Soviet spacecraft but for the zoom-way-in effect we all love we'll have to wait for the Mars Reconnaissance Observer to build up some data. Details here: http://marsprogram.jpl.nasa.gov/mro/
The articles linked aren't specific about mission details, but NASA planners acknowledge that a major problem on any Mars mission will be radiation exposure. Getting to Mars and back at all with chemical rockets requires either taking a long slow trajectory or using gravity assist from other planets, making any Mars mission more than a year-long prospect and exposing the crew to radiation beyond the allowable lifetime limits. The shielding method that stands head and shoulders above others is plain water. A double hull spacecraft with about a foot thick layer of water between the hulls would cut radiation exposure by more than half -- far better than anything else proposed. The water hull would also provide micrometeorite shielding. The outer few inches would freeze. If a micrometeorite penetrated the hull, water leaking out through the hole would freeze re-seal it immediately. The water hull would also provide an enormous heat sink that would eliminate the need for a complex refrigeration system to get rid of heat from human bodies and equipment. But to haul that much water weight around is beyond the current capabilities of chemical rockets.
One possible solution is to use nuclear rockets to get there and back. For sheer power they leave chemical rockets in the dust. A nuclear powered rocket would enable "point and shoot" missions, essentially aiming at the spot in the sky where the destination will be in a few months, overcoming planetary gravity by brute force. Here's an interesting article about a design for a fully reusable, non-polluting nuclear rocket based on the Saturn V form factor, that could lift one thousand tons of payload into Earth orbit and return intact to a powered landing. No solid fuel boosters, no jettisoned fuel tanks. Just a big rocket that takes off and comes back.
So you are claiming that, without the Moon landing, digital computers woudln't have been invented? Don't be obtuse. Obviously, nobody's claiming that. Technology has been an evolution, demarcated by the occasional revolutionary breakthough that ends up being a core component years later (tube, transistor, integrated circuit, etc). These are important, sure, but they aren't really what makes advances. Advances are made through necessity, real or imagined. Right now the "necessity" seems to primarly be entertainment driven, which is why you see so much R&D going into high-density storage.
In the 60s though, there was a different necessity: Beat the soviets to the moon. It was very important to a lot of USians, and the Kennedy administration had made it a big focal point. Science of course, had a different aim, but the political and social pressures drove funding.
There was a big perceived problem at the time, though. The soviets had "won" every aspect of the race in 1960. And they had the N1 on the horizon, whose heavy lifting capability easily surpassed anything that NASA or the army (redstone, vanguard, etc) had on the drawing table. Nobody knew, of course (or at least the public didn't), that the N1 had some serious design flaws that would later result in the worst disasters in the history of manned space flight (and that includes the two lost orbiters).
The workload of actually performing a moon landing was so intesive that it wasn't thought possible for two or even three men to do it with any reasonable safety or confidence. They knew they were gonna to use those new-fangled digital computers for guidance systems, control, environment, etc. Problem is, of course, nobody had ever built a small computer that was up to the task and there was certainly no software capable of handling all the tasks (often more than one simultaneously). Keep in mind, the overwhelming engineering pressure at all times was payload mass. Every kg you take up is another kg of fuel you can't burn, plus you have to add fuel to push that kg, so dropping a kg of payload is worth more than its weight in fuel.
In 1961, NASA formally chose the MIT Instrumentation Lab to produce the AGC (apollo guidance computer). This is in an era before the term "software engineering" had been coined. Nobody had ever written a piece of software like this before, its scope, at the time, was literally inconceivable. The were no development procedures, testing models, best practices, etc. Everything had to be created from scratch.
It almost didn't happen. In 1964, NASA came close to pulling the plug on MIT, because MIT was behind schedule and beginning to fully understand that the details where much more sophisticated than they had originally thought.
During this project, the MIT Instrumentation Lab operated as nearly a pure research facility. They documented their procedures and they shared knowledge with other research facilities. It was there, in that lab, that software development as we know it today was born.
Would it have happened otherwise? Probably. Not in the same way of course, and not at the same speed. Some of the conceptual leaps that were made w.r.t. software development might never have happened, because they might not have been perceived as necessary. One thing is for sure, the apollo program did change the face of the world in an area not directly related to space-flight. Speculating what might or might not have happened without apollo seems largely pointless.