like carbon nanotubes, or graphene that is only one atom thick, and thus transparent, but stronger than steel to block possible debris from destroyed objects. Plasma valve A related technology is the plasma valve, invented shortly after the plasma window. A plasma valve is a layer of gas in the shell of a particle accelerator. The ring of a particle accelerator contains a vacuum, and ordinarily a breach of this vacuum is disastrous. If, however, an accelerator equipped with plasma valve technology breaches, the gas layer is ionized within a nanosecond, creating a seal that prevents the accelerator's recompression. This gives technicians time to shut off the particle beam in the accelerator and slowly recompress the accelerator ring to avoid damage. Properties The physical properties of the plasma window vary depending on application. The initial patent cited temperatures around . The only limit to the size of the plasma window are current energy limitations as generating the window consumes around 20 kilowatts per inch (8 kW/cm) in the diameter of a round window. The plasma window emits a bright glow, with the color being dependent on the gas used. Similarity to "force fields" In science fiction, such as the television series Star Trek, a fictional technology known as the "force field" is often used as a device. In some cases it is used as an external "door" to hangars on spacecraft, to prevent the ship's internal atmosphere from venting into outer space. Plasma windows could theoretically serve such a purpose if enough energy were available to produce them. The StarTram proposal plans on use of a power-demanding MHD window over a multi-meter diameter launch tube periodically, but briefly at a time, to prevent excessive loss of vacuum during the moments when a mechanical shutter temporarily opens in advance of a hypervelocity spacecraft. See also List of plasma physics articles Tractor beam Other sources BNL Wins R&D 100 Award for `Plasma Window' Ady Hershcovitch. Plasma Window Technology for Propagating Particle Beams and Radiation from Vacuum to Atmosphere Bibliography Ady Hershcovitch (1995). High-pressure arcs as vacuum-atmosphere interface and plasma lens for nonvacuum electron beam welding machines, electron beam melting, and nonvacuum ion material modification, Journal of Applied Physics, 78(9): 5283-5288 References External links Official article by Ady Hershcovitch - Inventor of the Plasma Window. Brookhaven Lab Wins R&D 100 Award for the "Plasma Window" Brookhaven National Laboratory - Where the Plasma Window