Space.com (March 8, 2010)
"Captain Kirk might want to avoid taking the starship Enterprise to warp speed, unless he's ready to shrug off interstellar hydrogen atoms that would deliver a lethal radiation blast to both ship and crew.
"There are just two hydrogen atoms per cubic centimeter on average in space, which poses no threat to spaceships traveling at low speeds. But those same lone atoms would transform into deadly galactic space mines for a spaceship that runs into them at near-light speed, according to calculations based on Einstein's special theory of relativity.
"The original crew of "Star Trek" featured as unfortunate examples at a presentation by William Edelstein, a physicist at Johns Hopkins University, at the American Physical Society conference in Washington, D.C. on Feb. 13. The physicist showed a video clip of Kirk telling engineer Scotty to go to warp speed.
" 'Well, they're all dead,' Edelstein recalled saying. His words caused a stir among the audience...."
He's right, by the way. Sort of. Of course, they were never alive, except as fictional characters: a metaphysical tangent I will not get distracted by.
The article combines some reminiscing - Edelstein's son had asked about friction in space, some 20 years ago - and quite a bit of hard science.
About warp speed killing the crew? Well, that's sort of right. Assuming that the spacecraft is traveling through the three dimensions we're familiar with - four, counting time - as they approached speed-of-light, the rarefied vacuum of space would feel less empty. Those hydrogen atoms would be traveling past the ship at relativistic speeds.
Make that traveling through the ship. And the crew. And anything else on board. Unless they had enough shielding.
That's where it gets tricky. Apparently, "...A starship might need anywhere from a 4.4 -meter to 4,400-meter thickness of lead shielding to deflect the hydrogen radiation...." A ship that needs 4.4 kilometers of lead shielding to keep the crew alive could be a problem.
Giving the original Star Trek series credit, they did think about navigational hazards. That dish antenna on the original Enterprise was supposed to be a 'navigational deflector' - although the writers may have had largish chunks of rock, in mind, rather that the interstellar medium. And yes, I'm a fan of "Star Trek" from 'way back. Not a 'Trekkie,' but I like the show. Still do.
Edelstein is right, though. Anything going close to speed-of-light is going to experience hard radiation: sort of like being at the business end of CERN's Large Hadron Collider, mentioned in the article.
Assuming the ship is traveling through space, that is.
Warp Ships: No, Really
There's the alternative of isolating a pocket of spacetime and moving that through - or past? - the rest of spacetime. What's in the pocket is 'at rest' relative to local spacetime, so a ship there would experience no acceleration. A physicist named Alcubierre worked out the math for handling this sort of situation a few years ago.Even then, the spacetime pocket would be connected to the rest of our universe: and the intense shearing tidal effects at the interface would shred those hydrogen atoms and cause - noticeable - radiation.
The last I heard, physicists are still debating whether Alcubierre's warp drive would work, and whether it would be stable. One intriguing possibility is that the field would collapse, dragging the surrounding spacetime with it: you'd be left with a fair-size black hole.
When we get around to testing that thing, I hope someone has the good sense to put the launch area well outside the Solar system.
Or, that engineers and physicists have worked out the math adequately.
They'll probably have plenty of time to go over the numbers. The Alcubierre warp ships depend on our being able to create very intense, highly localized changes in the curvature of spacetime. One scientists speculated that we might be able to do that by making small black holes and then moving them very vast.
I don't think the first warp ships will be launched in my lifetime.
Construction at Spaceport America
Oh, well, there's plenty going on, closer to home. The Terminal Hangar Facility at Spaceport America is under construction, America now has seven spaceports, and several other countries have their own space programs up and running.As I've written before, this is an exciting era to live in.
Related posts:
- "Spaceport America: More Progress"
(January 29, 2010) - "America's Seventh Spaceport"
(January 19, 2010) - "Warp Drive Might Not Be Stable: Physcisists Take Another look at Alcubierre's Work"
(June 12, 2009) - "Warp Drive: Yes, it May Be Possible; But Don't Hold Your Breath"
(May 7, 2009) - "Anatoli Bugorski and the Proton Ray of Doom"
(February 7, 2009) - "Faster-Than-Light Travel: Maybe"
(August 14, 2008) - "Serious Discussions of Warp Drive"
(May 24, 2008) - "Interstellar Travel: Difficult, yes; Impossible; No - NASA"
(April 30, 2008)
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