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This is very unlikely to occur. No spacecraft can currently make this journey. The idea that you are going to design, build, launch, test, and then fly an entire system which is going to spend 517 days in space without resupply in less than 5 years, is likely a flight of fancy.
That's a mega-engineering effort which matches or exceeds the Apollo program (5 years from start to lunar fly-by, requiring >5% of the Federal Budget)
I wish them the best of luck, but I think that an unmanned flyby is the best we can realistically hope for. Next time around a landing is more likely.
... I think that an unmanned flyby is the best we can realistically hope for.
We have already done unmanned flybys. Unmanned landings as well. Unmanned 'rambling around' with rovers & strollers. Time for the next step.
It may not contribute much to science, but the couples names will be known unto the third millennium. I hope I live long enough to read about the first human circumnavigation of an outer planet.
We have already done unmanned flybys. Unmanned landings as well. Unmanned 'rambling around' with rovers & strollers. Time for the next step.
It may not contribute much to science, but the couples names will be known unto the third millennium. I hope I live long enough to read about the first human circumnavigation of an outer planet.
There is a very good reason why all our probes to Mars have been unmanned. It would be suicide to send a manned mission to Mars. Just the effects of zero-gravity alone will kill them. According to NASA for every week spent in zero-gravity, 2% of your muscle mass is lost. For every month spent in zero-gravity, 1% of your bone density is lost. Which means that on a 501 day trip astronauts will lose 16.5% of their bone density and 143% of their muscle mass.
This does not even take into consideration the radiation from the solar winds. Just one solar flare or CME in the astronaut's general direction, and they will be dead before they knew what hit them.
There are three technological challenges that must first be developed before we can even consider a manned mission to Mars:
Artificial Gravity - Either through thrust or centrifugal force.
Shields - Either electromagnetic or physical.
Propulsion - Something, anything, faster than chemical rockets (i.e., ion drives, nuclear engines, etc.)
We will get there, I have no doubt. However, this is not like a three-day trip to the moon, and I would rather not have the very first manned mission to another world end up in a fatality. There are a lot of people working on the three issues listed above. It may not happen within the next decade, but it will happen.
"According to NASA for every week spent in zero-gravity, 2% of your muscle mass is lost. For every month spent in zero-gravity, 1% of your bone density is lost. Which means that on a 501 day trip astronauts will lose 16.5% of their bone density and 143% of their muscle mass."
Political correctness has prevented the step we used to take - sending a monkey or dog or other animal on a one way trip and monitoring the effects of it. I suspect that the results of the trip might not be anywhere near as dire as you predict, and likely LESS of a problem that that experienced by people with rotating shifts. That said, I wouldn't want to be a child born to the couple after the trip.
Glitch is a grinch who probably lives alone in a log cabin in Alaska. He/she gainsays everything I post. I don't pay any attention to him/her, and neither should you.
Columbus was warned that he might sail off the edge of the earth!
"According to NASA for every week spent in zero-gravity, 2% of your muscle mass is lost. For every month spent in zero-gravity, 1% of your bone density is lost. Which means that on a 501 day trip astronauts will lose 16.5% of their bone density and 143% of their muscle mass."
Political correctness has prevented the step we used to take - sending a monkey or dog or other animal on a one way trip and monitoring the effects of it. I suspect that the results of the trip might not be anywhere near as dire as you predict, and likely LESS of a problem that that experienced by people with rotating shifts. That said, I wouldn't want to be a child born to the couple after the trip.
I do not see the point of sending some critter on a one-way mission when we already know the problems. We have had people in space long enough to know the effects of zero-gravity and cosmic radiation. They can mitigate muscle mass loss through exercise, but there is nothing that can be done to prevent bone density loss, except some kind of artificial gravity.
If they could accelerate at 1G half way to Mars, then decelerate at 1G the other half of the distance to Mars, they could make the trip in two days AND have the influence of a full 1G the entire way. That gets us back to the problem with propulsion.
Chemical rockets provide plenty of thrust, but are terribly inefficient. It would require massive amounts of hydrogen and oxygen in order to accelerate and decelerate the entire two days. While ion engines generate thrust for a very long time, the amount of thrust is extremely tiny, only 1/106,521.7 G (or 0.000092 m/s²).
A nuclear powered hydrogen fusion pulse engine could provide adequate thrust for the length of time needed, if one is ever built.
Shielding is still a problem. Several universities are currently working on different ways to shield the astronauts and the spacecraft from harmful cosmic rays. Physical shielding is the easiest approach, but also very expensive. Physical shielding weighs a great deal because it must be very dense to stop the radiation. The more weight, the more fuel required.
MIT is working on a electromagnetic skin for the ship that would create a magnetic field similar to Earth's magnetosphere in order to protect the astronauts and the ship. They still have a long way to go, however, because of the kinetic impact of the particles they are trying to stop it is like trying to stop a baseball moving at a 100 mph.
Like I said, we will eventually get a manned-mission to Mars, and get them back safely to Earth. This does not have to be a one-way suicide mission.
Another alternative to thrust generating 1G is by using centrifugal force. A torus, 1,500 feet in diameter, spinning at two revolutions per minute, would provide 1G of force. However, that provides some interesting engineering challenges. Such as, how do you transition from spinning 107 mph to 0 mph when moving to stationary parts of the ship?
Last edited by Glitch; 03-05-2013 at 02:55 PM..
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