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Scientists Work To Produce 'Star Trek' Deflector Shields
cold fjord writes "This might be useful. From CNN: 'Recent evidence from NASA's Curiosity rover mission to the Red Planet has revealed that astronauts on the round-trip would be exposed to high levels of radiation from cosmic rays and high-energy particles from the sun ... this would clearly be bad for your health — and it is proving difficult to find a solution. ... [S]hielding to completely block the radiation danger would have to be "meters thick" and too heavy to be used aboard a spacecraft. In contrast, ... science fiction fans have once again got used to the ease with which Captain Kirk gives the order for "shields up" and the crew of the Enterprise being protected instantly from the hostility of space. Perhaps though, a real Star Trek shield may no longer be science fiction — scientists at the UK's Rutherford Appleton Laboratory (RAL) certainly think so. They have been testing a lightweight system to protect astronauts and spacecraft components from harmful radiation and working with colleagues in America to design a concept spaceship called Discovery that could take astronauts to the Moon or Mars. "Star Trek has great ideas — they just don't have to build it," said Ruth Bamford, lead researcher for the deflector shield project at RAL. ... The RAL plan is to create an environment around the spacecraft that mimics the Earth's magnetic field and recreates the protection we enjoy on the ground — they call it a mini magnetosphere." Related: 'Deflector Shields' protect the Lunar Surface.'"
Amazing picture at the end of the article, be sure to not miss it.
Because Star Trek actually got it right that you would need shields for basic space travel, not just combat.
deflector shields (which was emitted by the deflector dish) which were low powered and meant to deflect small particles and radiation, and defensive shields which were to protect against weapons and were emitted by various shield emitters on the hull. The summary really badly conflates the two.
When in doubt, copy nature.
Only to idiots, are orders laws.
-- Henning von Tresckow
Space shuttles are low earth orbit only, they never leave Earths Magnetosphere anyway.
Moon capsules did leave the Earths Magnetosphere but weren't shielded. They were protected by limited time in space (2 weeks at most) and luck that they weren't hit by decent solar storm.
These comments are my personal opinions and do not necessarily reflect the opinions of the other voices in my head.
Calculate the area of the 2D projection of a ship onto a plane perpendicular to its line of motion, multiply by the length of space traversed to get swept volume...
Once you realize that this volume is always going to be enormous for any inter-planetary travel, even for a really really tiny craft, then you stop wondering why sometimes a probe that we send out suddenly stops responding for no obvious reason.
"His name was James Damore."
The Apollo missions had deep space radiation exposure of around 7-10 days. Their radiation solutions (which mostly amounted to not launching during a solar flare) aren't going to extend to journeys which last much longer than that.
Well, sorta. If you do enough technobabble and you're willing to count close enough as a hit, then getting it right isn't that hard.
Point in case, in ST's case the Navigational Deflector (emitted by the deflector dish) was actually supposed to protect against space debris, micro-meteorites, etc. (Still a good idea, mind you, because when you're moving even close enough to the speed of light, a single grain of sand packs more energy than a broadside from a 20'th century battleship.)
Dealing with particles via magnetic field was actually the job of the Bussard Collectors (you know, those red glowing things at the front of the nacelles), a.k.a., ramscoops. Which actually didn't deflect it, but collected all that mostly hydrogen in the ship's path.
So, yeah, if you make a complete hash of which did what, and how, and still call it a ST deflector shield, yeah, you can count it as a hit.
But then by the same lax standard I can claim that Jesus endorsed binary code. Matthew 5:37: "But let your communication be, Yea, yea; Nay, nay: for whatsoever is more than these cometh of evil." :p
(And yes, I'm a huge ST and SW nerd. I know, I know, I'll go not get laid now.;)
A polar bear is a cartesian bear after a coordinate transform.
The Curiostiy RAD experiement Principal Investigation gave a talk about Martian radiation 6/26 in Denver.
- 90% of the enroute radiation was from cosmic rays, the rest from solar flares. However a large solar storm could exceed cosmic ray levels.
- The eight month trip resulted in over 300 milliseverts of radiation, about one third of the recommend lifetime human dose.
- The thin Martian atmosphere greatly attenuates the surface radiation. But its still much higher than Earth.
- Hydrogen rich materials like water or certain plastics are useful barriers against cosmic rays. The ISS current has plastic shielded sleeping areas (to wait out solar storms too). It has been suggested to store fresh and waste water in the walls where the astronauts live and work.
To seek out wi-fi and new civilizations
Err, no. Both kinds were called deflector shields, in the canon. See: http://en.memory-alpha.org/wiki/Deflector_shield
The lower level one emitted by the navigationa deflector (a.k.a., deflector dish) dish was nothing else than a lower intensity force field, but still a deflector shield. (http://en.memory-alpha.org/wiki/Navigational_deflector)
A polar bear is a cartesian bear after a coordinate transform.
...and hot green alien chicks!
Any insufficiently advanced magic is indistinguishable from technology.
Obviously we must pour billions of dollars into this supper effective Luck shielding. If we can research enough Luck we don't need anything else.
"You saved 1968." - Ms. Valerie Pringle to the crew of Apollo 8
Active shielding (as opposed to passive shielding that uses more mass of materials) is not a new idea [1]. The Rutherford Appleton Group every other year or so contacts NASA saying, look what we can do. Annoyingly, they do the contacting of NASA through the State department occasionally... NASA looks at their design, says "Uh huh, have you done a tech. demo yet?"
RAL says, "Yes, here are the results."
NASA says, "Yes, but this is for 10 MeV electrons. Which are not really part of the space radiation problem. Where are the higher energy proton and heavy ion results?"
RAL says, "..."
Space radiation protection is fundamentally different from terrestrial radiation protection. Space radiation is much higher energy and consists mainly of protons (but also heavy ions are important due to the Z^2 effect of radiation dose). And it is omnipresent - you cannot get away from space radiation - it is everywhere.
See, the problem with the unconfined magnetic field work is that the size and mass of the equipment to make a magnetic dipole against cosmic rays is prohibitive. The most recent analysis that I know of is by Paluzek [2] and needs a million kg in equipment with a diameter of 100 meters...
A nice review of the science and engineering aspects of active shielding can be found in Townsend (2005) [1].
[1] Townsend, L.W., "Critical analysis of active shielding methods for space radiation protection," Aerospace Conference, 2005 IEEE , vol., no., pp.724,730, 5-12 March 2005, doi: 10.1109/AERO.2005.1559364
[2] M. A. Paluszek, “Magnetic Radiation Shielding forPermanent Space Habitats,” in The Industrialization of Space: Proceedings of the Twenty-third Annual Meeting, American Astronautical Society,36 Part 1, 545-574, 1978.
Mostly empty isn't good enough at the energies involved. It really doesn't matter what the probability for an impact is, since it is almost always going to be > 0. Even at the relatively pedestrian speeds of highway travel, a tiny pebble to the windshield does huge damage if it hits right.
... whatever
I thought a thin layer of matter was pretty good at stopping ionized particles such as alpha and beta rays, while you needed a thick slab of matter to stop gamma rays. An electromagnetic deflector will not interact with gamma rays. I'm getting an impression here that a deflector is only useful for cases where there's a cheap alternative.
It could probably deflect pretty powerful ionized particles though, because you can mount it at a long distance from your spacecraft so that a little bit of deflection is enough.
As a bonus, Roddenberry's First Law states that you can use a main deflector dish to do anything, so if they succeed in building this technology then we can also look forward to faster-than-light travel, instantaneous communication across distances of galactic scale...
If you disagree, post your argument. (-1, Overrated) isn't your personal censorship tool for views you don't like.
And you realize that Voyager 1 and 2 are frigging miracles that they are still alive after making it through the Oort Cloud and the trashbin that is our interplanetary space.
The Oort cloud is thought to extend out nearly a light year from the sun. Voyager 1 & 2 have most definitely not passed through it. But it's not like it's some super dense Star Wars style asteroid belt. You could fly a planet through it and not hit anything substantial.
No, they're not. The engineers and physicists knew all about cosmic radiation but there was nothing they could do about it. The shuttle does well enough since it stays within Earth's magnetosphere.
Apollo did leave the magnetosphere for part of it's mission and the Astronauts were exposed to radiation. They reported that they could see flashes of light believed to be caused by cosmic rays interacting with the fluid in their eyes. Had the sun flared at the wrong time, the crew would have been killed. Given the many risks of the Apollo mission, that was just one more and hardly the largest.
However, a mission to Mars with the crew in space for much longer can't take that approach.
The velocity of the craft does matter, and I will explain why.
If the velocity of the craft is much greater than the particles (think of dust floating in the air), then the craft will indeed sweep out all the particles in its line of motion.
However, the the velocity of the craft is much less that the particles (think cosmic rays in interplanetary space), then there will be the same number of collisions per unit time during the trip. A five hundred day trip will have ten times the number of collisions as a fifty day trip. Consequently, the faster your craft travels, the fewer particles you encounter during your journey.
It's not the magnetic field that''s the problem. Until you get EXTREMELY high anyway. Like, "rip the iron out of your blood" high. Or you have an implant with any ferrous material. (thankfully titanium isn't substantially ferrous)
The problem is the HEPs (High Energy Particles) that are flying out of the sun from CMEs (coronal mass ejections) at moderate speed. These are small atomic level particles, and are moving so fast and are so small that the odds of them ever hitting anything are very slim. But there's a lot of them. So it's like someone shooting at you with a shotgun from a few blocks away. But he's got a million shotguns. Odds are he's gonna get lucky eventually. It works the same as radiation. And when one of these "pellets" hits a strand of DNA, it'll break it up like a cue ball breaking a rack on a pool table. It will almost certainly prevent the cell from ever being able to divide, and will affect enzyme production, which may be fatal to the cell.
If there's enough HEPs flying your way, it's like getting hit with a high or massive dose of radiation. And massive DNA damage. There's also a lot of cellular damage, which the cells might be able to repair if they were working right, which they're not due to the DNA damage. So you get massive cell death throughout your body over the next few hours or days. Maybe enough to kill you. Or almost certainly give you cancer if you survive. Possibly a very nasty, widespread, aggressive cancer.
Aaaanyway, these particles are moving fast and there's a lot of them, but they're very light. And usually heavily charged from their explosive exit from the sun. Charged particles are very easy to influence with a magnetic field. So you put a magnetic field around an area, like the earth's magnetic field does around the earth, and the particles tend to route around the area instead of through it.
The aurora borealis is the visible effect of HEPs interacting with the earth's magnetosphere. When you can see that, there's enough HEPs hitting it to actually deform it. (cool videos of this effect on youtube) The shape of the field is very important. Notice how the north and south magnetic poles of the earth offer far less protection.
The earth's magnetic field protects us from this, so we didn't evolve a resistance to it. So when we leave its protection, we'll need to have something else to keep the HEPs from damaging our cells. And the best two theories going right now are blocking it and deflecting it. Blocking it is heavy, and heavy is never good when you're talking space travel. Deflecting it... well, it's tricky, they're working on it.
I work for the Department of Redundancy Department.