Yesterday we learned that physicists working on the ALPHA Project at CERN successfully contained a stable sample of antimatter--antihydrogen specifically--for 1,000 seconds this spring. Since the term "antimatter" first hit the pages of Nature in 1898, scientists have speculated over the possibilities of an opposing force of nature, a push to counteract the pull of Newton's gravity. The next hundred years would prove to be a century of dreaming what antimatter could do--from creating an infinite supply of renewable energy to producing for fuel intergalactic rockets. And as a dream has the idea largely remained since then as, despite mounting evidence for its existence, scientists could not produce and contain a sample antimatter long enough to study it. That is, until this month, they couldn't.
The recent 1,000-second achievement is about 999.8 seconds longer than physicists' first attempt to stabilize antimatter a year ago. Antimatter by its very definition is the antithesis of matter, as each of its parts is the opposite to the particles regular matter counterpart. So imagine one regular hydrogen atom, made up of a single proton and an electron. An antihydrogen atom would consist of an antiproton and a positron, a particle identical in mass to an electron but opposite in charge. When the two meet, the opposite particles annihilate each other in a huge burst of energy. At CERN, physicists successfully built a magnetic container for the antimatter particles using superconducters, and managed to keep the particles stable for the 16 minutes and 40 seconds--1,000 seconds.
This is all very exciting if you like science fiction. As NASA itself pointed out in 2006, antimatter is sci-fi writers' favorite starship fuel, and should physicists ever get the chance to study it more closely, it's the sort of thing to fuel fantasies about human travel to Mars. According to NASA, "while tons of chemical fuel are needed to propel a human mission to Mars, just tens of milligrams of antimatter will do," but since physicists have been unable to study antimatter in detail, safety concerns stand in the way of building an antimatter starship. However, the recent breakthrough at CERN could change all of this:
Another challenge is storing enough positrons in a small space. Because they annihilate normal matter, you can't just stuff them in a bottle. Instead, they have to be contained with electric and magnetic fields. "We feel confident that with a dedicated research and development program, these challenges can be overcome," said Smith.
If this is so, perhaps the first humans to reach Mars will arrive in spaceships powered by the same source that fired starships across the universes of our science fiction dreams.
The container CERN physicists created with superconducting magnets will enable them to study antimatter in far more detail than ever before. And with the recent discovery that antimatter is floating above thunderstorms on Earth, they may be able to harvest the obscenely rare particles more easily. Challenges aside, it's pretty cool stuff.