Being the long-time dork that I am, and having a fascination with spacecraft - fictional and factual - for as long as I remember knowing what a spaceship was, I'm always interested in seeing how far away we are technologically from the cool stuff we see on sci-fi.
A quick rundown of current deployed space technologies reveals a depressingly unexciting level of advancement. However, upon closer examination, we can see several advancements on the horizon, with some even closer than that. I'll outline some for you, approaching the numerous problems with long-term deep space exploration.
#1. The large distances between interplanetary bodies
This problem is most easily rectified by increasing the speed at which our spacecraft move. At present, the fastest human spacecraft is moving at a speed of 150 km/sec. At this speed, a spacecraft could travel from Earth to Mars in 6 months. Boooooooooooooooring. There are several drive systems in development which could make that time laughable, in just a matter of decades. One of them is the ICAN II, a propulsion system which uses a matter-antimatter reaction to produce a top speed of 600 km/sec, reducing Earth-Mars trip time to 1.5 months. Faster still is the Beam Core drive, a particle accelerator which - mounted as a pair of nacelles - would allow top speeds of 40 % lightspeed. The VASIMR drive is a more conservative option (300 km/sec), but which has the added advantage of throttleability. It is a more efficient, elegant solution, which may ultimately be the way we go with the proposed Bush CEV project.
#2. Radiation and particle protection during high-speed travel
Protection from random space particles during high-speed flight is crucial, not a sci-fi luxury. A solution to this problem is possibly via a side-effect of a propulsion system called the M2P2, developed by a Dr. Winglee. It is, in effect, a solar sail without the physical sail. The system generates a large magnetic field quite like that of the earth, that can be projected out in front of the ship to deflect particles in the craft's travel path. A targeting system that could evolve into one fast enough to counter all incoming particles may already be seen in the MTAS (Multiple target acquisition system) found in the Apache Longbow. The current MTAS allows the Longbow to acquire and fire upon 8 targets simultaneously, deploying a varying number of munitions to the targets. It is not inconceivable, that given the advancement in computing speeds, an MTAS capable of acquiring and engaging hundreds of targets per clock cycle could be developed. This should be sufficient for applications in all but the fastest speeds.
#3. The long-term detrimental effects of zero-gravity
This problem has vexed us for as long as we've been thinking about it. Rotational artificial gravity has its own health problems (chiefly the gradient from head to foot and slightly off-plumb effects on the human body), so the problem needs to be solved in another way. The Podkletnov device, first observed in 1992, has been shown by NASA scientists to be unreliable in a vacuum. This does not preclude its use in spacecraft, however. The Podkletnov device can be developed into one system which both provides smooth, strong artificial gravity field, as well as an inertial-dampening field to counter the effects of rapid acceleration and deceleration in space AND aircraft.
#4. Those damn solar panels!!
This is a power problem. Relying on solar power for space travel is like relying on wind power to ply modern sea trade routes. By simply switching to a nuclear isotope power system, we not only lose those damn ugly solar panels, we increase available power onboard ship by orders of magnitude. Whereas now files transmitted from the Mars Lander are transmitted in a rate measured in kilobytes/sec, an isotope power supply would allow transfer speeds of megabytes/sec. A fission reactor would increase available power by more orders of magnitude, allowing for longer and more rapid communications. Of course, work on fusion and matter-antimatter reactors is being done, and may yield more dramatic results by century's end.
#5. Hull or component damage from large bodies or large energy applications
This calls for highly-powerful shielding systems. The answer has been in front of us all this time. We can direct the travel paths of high-energy, relativistic particles - even antimatter - through the effective use of magnetic field interaction. In fact, the basic theory of the Penning Trap allows us to store antimatter in bottles using these fields. We have even considered using it to direct higher-energy drive exhaust away from the metal surface of an Orion spacecraft, thus elimintating the need to replace erosive plating.By applying this theory to the protection of the outer hull of a ship, we can administer a localized, powerful magnetic field to the area which needs protection, which would redirect a particle on a collision course harmlessly away. This administration, on a larger shipwide scale, could protect from the results of nearby explosions or energy applications.
Of course, for those of us for whom only the fastest will do:
There is the Alcubierre-Loup Warp Drive. Fernando Loup thinks he has resolved the immense power requirements of the Miguel Alcubierre Warp Drive of the mid-90s, and has come to America to cooperate with physicists on creating applications and technologies to his theories. He is quite confident in his interpretation of hyperspace as a 3-brane in nature.
Posted by MinutiaeMan (Member # 444) on :
I have a feeling I would find this article fascinating, if I had any idea what it was referring to at various points. Hyperlinks are your friend -- use them.
(Sorry, but without anything more than a rough description and your say-so, this just looks like more fictitious technobabble to me.)
Posted by Balaam Xumucane (Member # 419) on :
RE: Rotational Artificial Gravity
Clearly I've not researched this to any degree, really, but are the physiological effects of rotational artificial gravity really so bad? I mean obviously it's not a perfect solution, but is running on a treadmill with two bungee cords holding you down that much better? I mean if I'm wrong then someone please point me to an article telling me so, but I've always considered rotational gravity to be a fairly simple and elegant solution for dealing with the problems of long-term zero-gravity.
Posted by Sol System (Member # 30) on :
I'm not certain this thread is Starships & Technology material, being, as it seems, mostly unfictional.
Posted by TSN (Member # 31) on :
"Faster still is the Beam Core drive, a particle accelerator which - mounted as a pair of nacelles - would allow top speeds of 40 % lightspeed."
I'm not sure something that goes at 0.4c would be useful for transporting people over anything but a very long distance. I mean, how far would you have to have travelled before you had even accelerated to that speed?
Posted by Jason Abbadon (Member # 882) on :
quote:Originally posted by Sol System: I'm not certain this thread is Starships & Technology material, being, as it seems, mostly unfictional.
Certainly more fitting than the "Spot the MACO" thread in here. Posted by MrNeutron (Member # 524) on :
Since Irishman didn't see fit to lost references or give any context to the stuff he posted, here are links and descriptions of some of the technologies mentioned in his "cut and haste" job.
#1. The large distances between interplanetary bodies
"The Antimatter Space Propulsion team at Pennsylvania State University (PSU) have developed ICAN-II. This utilises a combination of antimatter and nuclear fission, using the antimatter to induce fission by allowing the antiprotons to penetrate the fissionable nuclei where they will annihilate with protons. This release of energy causes the nucleus to split, with the result of a greater release of energy than with standard fission. It is estimated that only 140 ng of antimatter will be required for a 30-day trip to Mars, which is significantly less than a beam core antimatter rocket."
I dunno to what was being referred to here, as all the references to Podkletnov I can find refer to a debunked antigravity machine, not any method of artifical gravity.
#4. Those damn solar panels!!
Sure, fission reactors and the like are way more powerful, but given the number of failed (kaBOOM!)launches I can understand why a lot of people are nervous about putting nuclear payloads in current lifting vehicles.
And a general reference to the real-world issues of interstellar travel on the Warp Drive When page. Posted by Jason Abbadon (Member # 882) on :
People in space?!? Heresy I say!
Seriously, nuclear payloads are *not* too dangerous -if launched from isolated areas. And in smallish quantities: launching agiant reactor is ahuge leap from a small muclear powered rover. Really, why not make the reactor modular so that when it lands it'll be able to be used by astronauts? We could (concievably) chop the weight of a manned spacecraft by sending most of their needed equipment in advance and the monk...er...astronauts last.
Launching nuclear powered stuff from the Florida coast is a cluster fuck waiting to happen though. Think New Mexico or someplace that radiation wouldnt affect too much....like Cleavland. Posted by Cartman (Member # 256) on :
quote:Originally posted by TSN: I'm not sure something that goes at 0.4c would be useful for transporting people over anything but a very long distance. I mean, how far would you have to have travelled before you had even accelerated to that speed?
Or 4800 astronomical units, 120 times farther out than Pluto...
Posted by Jason Abbadon (Member # 882) on :
At that speed and acceleration, you'd need one of those (still untested) "deflector shields" to prevent your ship from being destroyed by impacts. From things as small as a pea.
I cant imagine any of these creative ideas being tested on the same mission: too many variables. That means that even if all of these ideas somehow bear fruit, we wont see them in use together for many decades.
Posted by MinutiaeMan (Member # 444) on :
That antimatter propulsion link might be cool, if we could, oh, maybe find a way to separate antimatter from matter in the first place. That alone is probably going to take a couple of decades -- right now, the only reason we know antimatter exists is because we can detect the little BOOM it makes when it collides with the surrounding matter environment a micromicrosecond after it's created.
I do like the idea of using an electromagnetic field for a sort of primitive deflector shield to protect against miniscule space debris -- that's actually a very logical and IMO realistic possibility, assuming we can generate a magnetic field of that scale and power while at the same time pushing the whole dang ship at an appreciable speed...
Posted by Irishman (Member # 1188) on :
Actually we've been making antimatter and collecting it in the aforementioned Penning Trap for going on 25 years. The CERN and Fermilab particle colliders have been manufacturing small amounts of antiprotons, more recently whole atoms of antihydrogen, which is easier to store. Not enough ot use on an interplanetary trip, but we're getting there.
Posted by Irishman (Member # 1188) on :
Also, while I'm at it, the Podkletnov device was debunked, but never disproven. What scientists disagreed on was the nature of the effect. Podkletnov argues to this day that it is a gravity-neutralizing effect that was observed, while more conventional scientists claim that it was the long-known "Ion wind" effect, chiefly because it doesn't work in a total vacuum. Podkletnov's experiments extrapolated that its effects were felt by non-metallic objects, over long distances.
Posted by MinutiaeMan (Member # 444) on :
quote:Originally posted by Irishman: Actually we've been making antimatter and collecting it in the aforementioned Penning Trap for going on 25 years. The CERN and Fermilab particle colliders have been manufacturing small amounts of antiprotons, more recently whole atoms of antihydrogen, which is easier to store. Not enough ot use on an interplanetary trip, but we're getting there.
Trapping a handful of antimatter atoms inside a magnetic field in a compartment that's built into a massive, kilometers-long particle accelerator is a very, very far cry from putting those atoms in transportable containers that can be launched in rockets with little chance of letting said antimatter get out and blow everything up.
Posted by Irishman (Member # 1188) on :
True, but we do store them in transportable containers. That is what the Penning Trap was made for. Assuming we got government go-aheads, we could transport a Penning Trap full of antimatter to orbit to waiting ship via Shuttle tomorrow. Plus, we can store antihydrogen much more densely than individual atoms of antiprotons, with a far lower expenditure of energy applied to magnetic containment.
Posted by MinutiaeMan (Member # 444) on :
Transportable containers? Pull the other one. You'd need a huge power source for the magnetic field plus its backup (since no one wants an antimatter explosion anywhere). They don't have that kind of heavy-duty portable power generation yet.
Besides, people are already up in arms about transporting radioactive nuclear waste across the national interstate highway system. That's generally a passive threat with only low-level danger. Can you imagine what people would say about transporting something equivalent to an armed fusion bomb through densely populated areas?
Posted by Balaam Xumucane (Member # 419) on :
ZPE or bust...
Posted by Austin Powers (Member # 250) on :
@Irishman: You talk about "we". "We can do...". Do you work at CERN or a similar laboratory - or are you just citing info from science maganzines?
Posted by Jason Abbadon (Member # 882) on :
The Irishman collective.
Posted by Davok (Member # 143) on :
quote:Transportable containers? Pull the other one. You'd need a huge power source for the magnetic field plus its backup (since no one wants an antimatter explosion anywhere). They don't have that kind of heavy-duty portable power generation yet.
I had a lecture today about antimatter propulsion given by a postdoc who had recently spent several months at CERN. He said it would be absolutely no problem to transport up to 1012 antihydrogen atoms in a penning trap. He also said he had planned to transport a trap from Geneva to Stuttgart to prove tranportability, which only failed since CERN stopped producing antihydrogen. Concerning "huge power source", he said a 9V-battery would suffice to sustain the magnetic field needed to confine antihydrogen at 4K!!
Posted by Irishman (Member # 1188) on :
Thanks Davok for the reinforcement.
Any way, I have a link here for further information on all the propulsion types I mentioned.
There's technical summaries on plasma core, beam core, ICAN, Orion, Mini MagOrion, Ion drives, etc.
Also, I read today that the X-33 is going to be the planform for the President's CEV to the moon and Mars. And it is going to be nuclear-powered, very much like our nuclear submarines.
Posted by MinutiaeMan (Member # 444) on :
quote:Also, I read today that the X-33 is going to be the planform for the President's CEV to the moon and Mars. And it is going to be nuclear-powered, very much like our nuclear submarines.
Can you say "pipe dream"? At this stage in the game, there are many, many problems with that assertion. First, for the CEV the folks at NASA are looking for a small, simple vehicle using existing technology for practical purposes. With the meager funding that Dubya's proposing, they're not going to be inventing new branches of theoretical physics to propel this ship. And there's no way in hell people would accept a nuclear reactor on one of those things. Think of the uproar from the Greenpeace people when Cassini was launched towards Saturn? After the loss of Columbia, nobody's going to want to have a nuke reentering the atmosphere.
Davok: Just 9 volts? I'd love to see a link to corrobrate that -- if so, it'd be amazing! (BTW, I'm not being negative here, just very skeptical and disillusioned with the current pace of scientific advancement.)
Posted by J (Member # 608) on :
A nuclear power generator might be feasible for the vehicle that would transport a crew from Lunar orbit to Mars orbit [along with a Martian Landing & Low Orbital Vehicle--- perhaps something like the CEV which could carry the crew to the ship that would then carry them to Mars].
I believe, that the real advancement for space travel is going to be the rail-gun launch system. However, the real benefit of this system is going to come from a Lunar base that can transmit power back to an energy hungry Earth. Once that is in place, this rail-gun would be a much better option than using chemical propellant. Of course, reentry is still a mess, but it's always going to be like that.
Posted by Cartman (Member # 256) on :
Well, as long as we're all fantasizing...
Just build an orbital tether and launching stuff becomes trivial, then slap a few docking ports on it and the reentry of said stuff becomes moot altogether.
Posted by Irishman (Member # 1188) on :
Actually, the only reason the X-33 was cancelled was because it couldn't function as initially conceived - a single-stage-to-orbit vehicle. In its new incarnation, I suspect they'll simply change out the aerospike engines for something with a higher Isp (specific impulse) like a VASIMR, and strap on some Energia booster rockets to get it into LEO. There are no revolutionary technologies that would be required to make it work, folks.
An orbital tether that someone could plant charges on, or ram a plane into? That's safe. What happens when the broken tether whips to the ground at many thousands of miles per hour??
The X-33 IS small. The plans I've seen call for a 40 meter long and wide vehicle. The shuttle is longer than that when it launches.
Posted by Cartman (Member # 256) on :
Right. And what happens when a nuclear-powered X-33 goes boom? What happens when a Penning Trap full of shall we say slightly explosive antimatter collapses while aboard one? You think THAT would be a pretty sight?
Posted by MinutiaeMan (Member # 444) on :
quote:Originally posted by Irishman: [QB] Actually, the only reason the X-33 was cancelled was because it couldn't function as initially conceived - a single-stage-to-orbit vehicle. In its new incarnation, I suspect they'll simply change out the aerospike engines for something with a higher Isp (specific impulse) like a VASIMR, and strap on some Energia booster rockets to get it into LEO. There are no revolutionary technologies that would be required to make it work, folks.
And the kind of spacecraft you're describing is drastically different from the X-33. The X-33 was designed to be a full Space Shuttle replacement, including some cargo capacity (albeit less volume). The proposed CEV is nothing more than a manned pod -- the Volkswagen Beetle to the X-33's school bus or the Space Shuttle's 18-wheeler. Once you change a craft design enough, it becomes something completely different. It may look like the X-33, but it won't be the same design by a long shot.
Hell, according to CNN reports, the CEV may not even be a reusable craft anymore -- NASA is considering the possibility of returning to the older launch strategies, at least for the short term.
Not to mention that those Energia booster rockets you mentioned were seriously flawed designs in and of themselves. I certainly have no interest in launching our next-generation manned spacecraft with 1980s-era Soviet rockets!
Posted by Austin Powers (Member # 250) on :
Russian technology isn't as bad as you would want to believe.
The Buran orbiter for example had quite a few advantages in comparison to the Space Shuttle. It was even able to complete fully automated missions as proven on its one and only testflight. The main reason why no one heard anything about it ever after was lack of funding after the USSR crumbled.
Posted by Wraith (Member # 779) on :
Unfortunately, many of Russia's larger rockets had a tendancy to go bang on the launch pad, although much of the stuff they're actually using now is pretty good, I wouldn't trust Energia!
Most of the speculation about the CEV that I've seen suggests that it will be non-resuable. Can you imagine the protests if there was a nuclear reactor being launched every few months from Florida?
Also, I *really* don't think it'd be a good idea to stick an antimatter reactor on a manned spacecraft without giving it some serious testing first. Preferably somewhere around Neptune.In any case, for manned missions, it really doesn't matter how powerful your engine is or how long it can burn; you can only accelerate at low Gs for significant amounts of time. Also, what is the maximum G-force the human body can take, and for how long?
Posted by Cartman (Member # 256) on :
9 to 12... for a minute or so. More if submerged in liquid.
Posted by Irishman (Member # 1188) on :
Replies to several issues.
Number one - the issue is not whether or not to have nuclear power (there are 436 nuclear power plants operational worldwide, most of which went online between the 1970's and 1990's - check the www.nrc.gov and other sources). It's not even whether or not to have nuclear power in space (the Cassini probe did that years ago). For the short 10-20 minutes the reactor would be in atmospheric flight from the launchpad to LEO, the risk would be minimal. There are nuclear reactors in navy submarines and carriers, even fusion reactors scattered across the globe at various research labs. There is antimatter being used in medical scans every day (via the Positron Emission Tomography), which functions through controlled Matter-Antimatter collisions.
Number two - a spacecraft equipped with a Podkletnov artificial gravity/inertial cancellers would not be limited to a 1g delta v. Accelerations would be limited only by the energy levels produced by the drive (in this case I think we were discussing a beam core antimatter drive). As for testing, of COURSE it would be tested! My God above!
Number three - regarding the relative danger of a nuclear-powered or m/ar-powered craft, the last I checked, the space program is a volunteer organization, at least in America. Noone is forced to be put in these dangerous situations. Yet, if we do not take great risk, we will not acheive great things.
Number four - the Energia was just an example given. I could just as easily have suggested a Proton booster rocket. The point was that booster rockets could assist the VentureStar into LEO.
Posted by MinutiaeMan (Member # 444) on :
quote:Originally posted by Irishman: [QB]For the short 10-20 minutes the reactor would be in atmospheric flight from the launchpad to LEO, the risk would be minimal.
And only slightly increased by the ignition of many thousands of tons of chemical explosives directly underneath it? Sure, that's the ticket!
And I take it you've got an extremely short memory for you to forget that reentry can be a dangerous time too. Take a look at some of the news footage of the Columbia going down. They found debris from the shuttle across an area 380 by 230 miles -- that's 87,400 square miles. Would you want to risk the possibility of a nuclear reactor traveling at Mach 18 and raining down on your civilian population? I think not.
quote:the last I checked, the space program is a volunteer organization, at least in America. Noone is forced to be put in these dangerous situations.
I'm talking about the danger to bystanders, not the crew themselves.
Look, I have the same sentiments as you -- we need to keep pushing out into space, we need a motivated volunteer astronaut corps, and so forth. But I think you're vastly overestimating both our practical technological capabilities and the government's ability to put it to use.
Posted by Davok (Member # 143) on :
quote:Originally posted by MinutiaeMan: Davok: Just 9 volts? I'd love to see a link to corrobrate that -- if so, it'd be amazing!
Sorry, I don't have a link. But keep in mind that 1012 hydrogen atoms would weigh no more than 10–15 g.
quote:Originally posted by Cartman: What happens when a Penning Trap full of shall we say slightly explosive antimatter collapses while aboard one?
Actually, not much. The probability for a proton and an antiproton to annihilate each other isn't that high if you don't confine them into a reaction chamber. And even if they annihilated, they wouldn't immediately become gamma rays (like electrons would) ... they'd rather decay into pions, which would leave your spacecraft without interacting with the "normal" matter.
quote:Originally posted by MinutiaeMan: Would you want to risk the possibility of a nuclear reactor traveling at Mach 18 and raining down on your civilian population? I think not.
Of course you would have to wait until the reactor is in LEO before making it critical... and you'd have to put it into a capsule that could survive catatstrophic reentry without breaking or becoming critical. I think all that is technically possible, but it would still be very, very hard to convince the public.
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