Scientists in Costa Rica set plasma engine record

SAN JOSE, Costa Rica (Reuters) - Scientists in Costa Rica have run a plasma rocket engine continuously for a record of more than four hours, the latest achievement in a mission to cut costs and travel time for spacecraft.

The Ad Astra Rocket Company, led by Costa Rican-born former NASA astronaut Franklin Chang-Diaz, said on Wednesday it hopes to use its rocket engines to stabilize space stations in a few years, and then to power a trip to Mars within two decades.

"The first objective is to move small spacecraft in low orbit by 2010," Ad Astra executive director Ronald Chang-Diaz, the astronaut's brother, told Reuters.

In December, the scientists ran the engine for two minutes but had to turn it off because it was overheating. They have spent much of the past six months designing cooling systems.

Scientists believe propulsion engines that run on plasma, a material composed of atoms stripped of electrons and found in high-pressure and -temperature environments like stars and lightning bolts, will be faster and cheaper than rockets currently used in space travel.

Considered the fourth state of matter because it is neither a solid, liquid or gas, plasma can reach millions of degrees, making it a potentially light but powerful fuel.

It is hoped that the engine, which uses Variable Specific-Impulse Magnetoplasma Rocket technology conceived in the 1970s, could eventually cut travel time to Mars by about a third, to around three months.

Scientists at Ad Astra's Houston laboratory are conducting tests aimed at boosting the engine's overall power, while in Costa Rica they focus on endurance, Ronald Chang-Diaz said.