NASA exploring laser beams to zap rockets into outer space
Baku, January 29 (AZERTAC). Space launches have evoked the same image for decades: bright orange flames exploding beneath a rocket as it lifts, hovers and takes off into the sky, Foxnews reports. But an alternative propulsion system proposed by some researchers could change that vision.
Instead of explosive chemical reactions onboard a rocket, the new concept, called beamed thermal propulsion, involves propelling a rocket by shining laser light or microwaves at it from the ground. The technology would make possible a reusable single-stage rocket that has two to five times more payload space than conventional rockets, which would cut the cost of sending payloads into low-Earth orbit.
NASA is now conducting a study to examine the possibility of using beamed energy propulsion for space launches. The study is expected to conclude by March 2011.
In a traditional chemical rocket propulsion system, fuel and oxidizer are pumped into the combustion chamber under high pressure and burnt, which creates exhaust gases that are ejected down from a nozzle at high velocity, thrusting the rocket upwards.
A beamed thermal propulsion system would involve focusing microwave or laser beams on a heat exchanger aboard the rocket. The heat exchanger would transfer the radiation's energy to the liquid propellant, most likely hydrogen, converting it into a hot gas that is pushed out of the nozzle.
With the beam shining on the vehicle continually, it would take 8 to 10 minutes for a laser to put a craft into orbit, while microwaves would do the trick in 3 to 4 minutes.
Another cost advantage comes from larger payload space. While conventional propulsion systems are limited by the amount of chemical energy in the propellant that's released by combustion, in beamed systems you can add more energy externally. That means a spacecraft can gain a certain momentum using less than half the amount of propellant of a conventional system, allowing more room for the payload.
Other news in this section
