Friday, May 05, 2006

Like Oil And Water

With the potential to get us to the stars.
Antimatter-Rocket Plan Fuels Hope for Star Trek Tech: "However, in a series of papers published in the journals Physical Review Letters and Physical Review in 1997 and 1998, a team of German and U.S. theorists calculated that the right combination of electric and magnetic fields would stretch out the positronium like a barbell and greatly reduce the probability of the electrons and positrons annihilating.

'We've done the calculations,' Smith said. 'And it's not uncommon to find that the lifetime [of the enhanced positronium] is [practically] infinite.'

Smith says that Positronics has begun experiments to verify their calculations, although he says the data from the experiments is not yet for public consumption.

Roger H. Miller is a professor emeritus of physics at Stanford University in Palo Alto, California. He has seen Smith present his publicly released data and is skeptical.

'The details are not available, so we don't know how many positronium atoms were stored, what their lifetime was, and how these quantities were measured,' Miller said via email.

One undisputed fact is that, if a storage tank could be created that keeps the positronium in a stable state, an astonishingly small amount of positronium would power a spaceship.

Ten milligrams (0.0004 ounce)—the mass of a grain of rice—would be sufficient to take a manned spaceship to Mars. Mere grams would be enough to fuel a hundred-year expedition to the nearby star Alpha Centauri.

Creating those milligrams of antimatter would be very difficult and expensive, however. Smith, of Positronics, estimates that a dedicated 1.5-billion-U.S.-dollar facility could churn out the positronium needed to go to Mars in three years.

Stanford's Miller, on the other hand, counters that 'the most powerful positron source ever built [so far] would take about 300 years to produce enough positrons.'

From Power to Propulsion

Positronium is ultimately just a very compact power source. Converting that power into propulsion is another crucial hurdle.

Under their more public NASA grant, Positronics Research has released specifications for a rocket that consists of a surface coated with silicon carbide—also known as Moissanite, a diamond-like substance that glistens atop rings and pendants on late-night television shopping networks.

The positronium in this proposed rocket would be shuttled from the fuel tank to the engine core, where it annihilates, producing two gamma rays that evaporate silicon carbide from the nearby surface. The resulting silicon carbide gas, then, becomes the exhaust that propels the spacecraft forward."
From a respected magazine! Please let it happen in my lifetime, in 1969 I thought we would be traveling the universe, not trying to salvage a major city from a foreseen disaster.

No comments:

Post a Comment