I love this stuff, but seriously … WTF?
The internet has been having frothy multiple orgasms all week over yet another NASA public relations stunt. The big accomplishment is that they hired artist Mark Rademaker to create really really sexy pictures of a starship that doesn’t exist and almost certainly never will. I’ll link the Gizmodo article, but just Google the damn thing. It’s on every seedy news rag from CNN to Huffington Post.
NASA has a long history of pumping up bizarre shit for publicity, usually around the time they are asking for more money. Unlike some of NASA’s past PR debacles (e.g. the Martian meteor that didn’t contain alien fossils after all, and the arsenic based alien life form that contained no arsenic). In this particular case though, the science — or at least the math — is sound. NASA’s Dr. Harold “Sonny” White actually sounds like a pretty cool guy, which alone sets him apart from the stars of past NASA spasms of public relations stunts. The only problem is, certain inconvenient truths aren’t quite making it to the media sites. Huffington Post and CNN have just been creaming themselves over statements by Dr. White to the effect that a prototype of this starship could be built in as little as ten years. What those bastions of investigative journalism aren’t publishing are the follow-up statements by Dr. White along the lines of “… and if we had some magical fuel to put in the gas tank, it might actually work!”
The starship needs two things that don’t exist in order to work:
- Exotic matter with negative mass.
- A substantial quantity of antimatter.
The first item on the list, exotic matter with negative mass, doesn’t exist at all beyond weird quantum effects under certain conditions. You’ll never get to eat a negative apple, for instance. But just sweep that one aside for a moment and consider the more mundane challenge: antimatter. Reading internet comments on these news stories, I see a lot of comments along the lines of: “We can already make antimatter, so just ramp up production.” Pfft! What’s making a little antimatter anyway, right? Piece of cake. For fuck’s sake!
A small starship of the kind proposed by Dr. White would require about 1,000 kg of antimatter. Antimatter is produced a few particles at a time in the Large Hadron Collider. Aside from the obvious problem that a few particles is a long way from 1000 kg, those particles are produced traveling at near the speed of light, so you can’t just pluck them out of the vacuum with a magical pair of forceps and toss them into a bottle. You’ve got to slow them down and keep them magnetically contained, and you have to “quench” them to produce some form of stable, non-plasma antimatter. By quench, I mean turn them into atoms. Let’s say you’ve produced a bunch of antiprotons in the collider. You’ll want to produce an equivalent number of antielectrons (positrons) as well. Then you’ll want to stream the positrons into the contained antiprotons in order to produce the simplest possible element you can make: antihydrogen. Let’s say you can make a huge amount of that, like ten milligrams … you still have to keep it contained and that ain’t gonna work.
The problem is, what you really need is antilithium. I don’t mean dilithium crystals like in Star Trek, but the antimatter variant of ordinary lithium. Why? Because it’s the lightest possible element that you can make that is a solid. Lithium is the lightest metal and the third lightest element on the periodic table after hydrogen and helium. Being a solid, you could probably contain a good sized chunk of antilithium in a special container that prevents it from making contact with the container walls. But … how do you get antilithium? You don’t. You could, I suppose, make tremendous quantities of antihydrogen and then create antihelium in a nuclear fusion reaction of your antihydrogen. And then you could force some of your antihelium to fuse in another antimatter nuclear fusion process … but come on! It ain’t gonna work!
This stuff is interesting to me for a variety of reasons. One of those reasons is that this is great fodder for science fiction stories. But there’s an old saying that goes something like this:
Fantasy is the impossible made possible;
Science fiction is the possible made probable.
I’d have to put the antimatter in the fantasy end of that spectrum. In fact, it’s easier for me to accept as science fiction the negative mass exotic matter that is required for the Alcubierre-White Warp Drive. There’s not too much known about exotic matter with negative mass. As such, it is kind of spooky and mysterious and you have to think: “Well … it could be possible …” Exotic forms of matter are like dark energy and dark matter: You don’t know much about them, you don’t know if they really exist, and likewise you don’t know that they don’t exist. In the case of antimatter though, too much is known about it, and what is known tells us this won’t be a fuel source available to humans anytime in the next 10,000 years.