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To Mars and Back in Ninety Days
paltemalte writes "A new means of propelling spacecraft being developed at the University of Washington could dramatically cut the time needed for astronauts to travel to and from Mars and could make humans a permanent fixture in space. In fact, with magnetized-beam plasma propulsion, or mag-beam, quick trips to distant parts of the solar system could become routine, said Robert Winglee, a UW Earth and space sciences professor who is leading the project."
I hate to be a buzzkill, but is there ANY realistic reason why sending people to Mars is good science?
It seems that if we spend the money that it would take to develop the spacecraft & lifesupport required to send people that far on better and more reliable robots, a lot more actual research would get done. Heck, we might even have enough left over to fix the Hubble.
Let's work on practical reasons to send people into space at all... then maybe the moon. Billions of tax dollars shouldn't be blown on a project of little scientific validity just because "it's cool."
In Capitalist America, bank robs you!
Wave a plan near congress and they're sure to kill it before breakfast.
Sure they will. The aliens don't want our crap in outer space at least until we can handle our problems like adult persons instead of reacting emotionally to every single difference between us. So, what's better than keep tabs in the govment of the only country that can fund such stuff?
It's better to be the foot on the boot than the face on the pavement. ~~ tkx Kadin2048
With a space elevator, of course ;)
Has anyone gleaned from the article how the beaming stations are maintained in place?
I got that nuclear and solar power would be used to generate the beam, but generating the beam would impart thrust to the station.
Did I miss something?
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What you do today will cost you a day of your life
..or at least the brakes. It's not a new plan, though it might be a new flavor. Nivens was talking about laser-based launching stations back in the 70s and he was just taking the most probable solution.
Of course Newton's laws interest me. If you fire an energy beam able to move a 1000kg probe at 11.7km/s, your 10,000kg station is going to be moving 0.117km/s. (261mph)
Then there's the power issue. Exactly what are these orbital launcher going to use for power? I don't see the green club letting enough fissionable materials get up there and otherwise we're looking at a biiiiig solar array tied to some form of energy storage (water/hydrogen/fuelcell?)
I've been on slashdot so long I'm starting to get out of touch with the cool stuff if it ain't on slashdot.
Please cite any source that claims a 30 minute-long fatal exposure dose for any near-Earth location.
As I understand things, from (among other books) Zubrin's "The Case For Mars" as well as ample proof from the ISS and our own Apollo moon missions, merely being in space does not mean fatal radiation doses are inevitable.
Rather, space travel does involve higher doses than one would receive on the ground, or (say) in a mineshaft. But that doesn't mean these doses are fatal, or even that they significantly impact long term health.
I remain interested if ANYONE can cite specific data (hopefully from a reputable source) saying that radiation doses in space are near fatal in the time frame envisioned for a Mars mission or, or any other popularly conceived-of mission aside from a manned mission to Jupiter, which does have significant radiation belts.
Unitarian Church: Freethinkers Congregate!
I'm not going to analyze every single item on your list...
But the Printing Press? Did you think this through? Do you really think Johann Gutenberg's motivation was profit??? Have you ever read Henry Ford's writings on business organization? He was a far more ardent critic of international finance than me.
I think you need to read a little more about the people who invented the items you are discussing. Most were invented by men who followed their dreams and were hardly concerned with financial gains. More importantly, financial concerns did not dictate whether or IF they pursued that dream.
I don't read or respond to AC posts
I'm an engineer.
If you put me in charge of a Mars mission here's the only proper way to do it.
#1 what we did in the sixties, whistle stop one pass visits, are pointless, if you're going to go then go, don't fuck around.
#2 we have the perfect platform for solar system operations right on uor doorstep, Luna, that and the L1 and L2 largrange points in lunar orbit for stuff that the moon's 1/6th gravity will make difficult or expensive.
#3 all space vehicles will need enough delta vee to decelerate to matching velocity with the target, whether that target is Mars, another planet, or an asteroid, that's no big deal we can use MHD which will efficiently generate low braking thrust for long periods.
#4 all space vehicles and this includes "materiel" of any kind, including "lego" style construction sets and so on, can be given practically any velocity you like by launching from a lunar linear accelerator, these work REALLY well in a vacuum.
SO top priority will be getting mebbe 500,000 tons of mass up to the moon to buind a nearly self sufficient base.
Best way to do that is a two pronged approach.
1/ Develop REALLY heavy lifters, nuclear salt water is cool as a starting point, first step need to be throw everything at perfecting Fusion until it's as doable as fission power plants.
2/ Develop (materials) for the space elevator.
The united states spends 450 BILLION dollars every year on the military, if that lot was thrown at this project you could adopt a JFK / Apollo sort of timescale and we'd have a viable and working moonbase by 2020 AD easy.
If the USA doesn't do this, there will be a moonbase by 2050 at the latest, and it will be Chinese.
When that happens the entire might of every military on the planet, IN CONJUNCTION, will be as effective as wet toilet paper agauinst a
Who knows, I may even live long enough to see it.
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Nanotubes aren't difficult to manufacture. It's nanotubes of appropriate length and consistency that are hard to manufacture. The current record is a mere 4cm, a little too short to reach orbit, even when wound as a cable. It's still several times longer than the previous record. If we can keep up this pace, we might be able to get nanotubes with lengths of tens or hundreds of centimeters soon, and those might be enough to wind into a cable. Imagine someone suspending himself from the ceiling with something the diameter of thin-guage fishing line.
Heh... Imagine catching a marlin with the same line.
Anyway, we still have some things to do, but we may be getting close to the point where we're not trying to peer over the horizon because the next major port is in view.
You can never go home again... but I guess you can shop there.
So here's an idea. Put a captured asteroid into an elliptical orbit. Perigee is at about 200 miles, going about 10 km/sec, apogee is at about 18000 miles going about 1900 km/sec. As the asteroid approaches perigee, it lowers a cable (made of space-elevator rope) into the upper atmosphere. As the cable gets into the atmosphere, the asteroid starts paying it out very fast, so that the end moves slow enough to be grabbed by a high-altitude airplane and attached to a spaceship. Once attached, the asteroid pays out cable slower and slower, accelerating the spaceship to the asteroid's velocity, and very slightly slowing the asteroid in its orbit. Eventually the asteroid starts reeling in the cable faster and faster, accelerating the spaceship further.
The spaceship only needs to be accelerated a little past the asteroid's velocity to reach escape velocity. There are a few possible ways to correct the energy loss of the asteroid's orbit. The simplest is for the airplane to attach a fuel tank to the cable along with the spaceship so that after the spaceship detaches, the asteroid can reel in the fuel and do a burn to pump its orbit back up.
Of course there's a big PR battle to be fought, to make people feel good about a big rock in a relatively low orbit over the earth. But if it worked, it would use a lot less rope than the space elevator, and it would get you into space quicker.
WWJD for a Klondike Bar?
One of the concerns of Freeman Dyson, one of the originators of Orion was that the radiation placed into the atmosphere by a single launch produced a statistical guarantee that 10 people somewhere in the world would get cancer who otherwise would not have.
But that wasn't what killed the project. What killed the project was the Nuclear Test Ban treaties of the 1960's. The Orion team actually felt that they could reduce the fallout further, potentially to levels where no one would die from a launch. This was due to the fact that the Orion actually attempted to contain its explosions rather than the military goal of causing the maximum damage possible.
Truth be told, if Red Mercury really does what it's supposed to (the Russians ARE selling the stuff), we may have a way of making Orion launches 100% safe. Of course, our government claims that Red Mercury is a hoax all the while other countries are buying the stuff up. Hmm...
Speaking of which, does anyone know what the heck Mercuric Pyro-Antimonate is useful for besides "creating" Red Mercury? There appears to be a whole bunch of the stuff on the open market, but no documents actually stating what it's useful for.
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