Vasimr Plasma Rocket Advances

This engine is of course veryimportant for working in space in the near future, particularly if Focus Fusionpulls off their fusion engine.  Then wehave the power to operate these engines continuously for years. That means thatthe design objective of operating a large craft under one G of accelerationbecomes plausible and the entire solar system is completely open toexploitation.

The purpose of one G craft isthat it becomes possible to send crews on long missions to the edge of thesolar system and back without endangering them. Such craft could also easily carry a rotating torus for the crew toprovide internal gravity when the craft is not under acceleration.

Once the energy problem is solvedthese problems are mere engineering problems. The first big step is the creation of good working plasma engines todrive it all.

VASIMRVX-200 plasma rocket achieves full power efficiency milestone

NOVEMBER 24, 2010

http://nextbigfuture.com/2010/11/vasimr-vx-200-plasma-rocket-achieves.html

Ad Astra Rocket Company’s VASIMR® VX-200 rocket prototypedemonstrated its highest power efficiency and performance so far in tests,which ended Friday November 19 at the company’s Houston laboratory. Last week’s results metthe efficiency milestone set by the company as it specifies the requirementsfor the VF-200 flight engine for the International Space Station.

At 200 kilowatts of power the plasma rocket delivers 5.7 Newtons of thrust at 72% efficiency andexhaust speed of 50 kilometers per second.

Many of the flight applications at the heart of our business model –orbital debris removal, satellite servicing, cargo flights to the Moon andMars, and ejecting fast probes to the outer solar system – have required thatthe propulsion system achieve 60% system efficiency at 50 km/s exhaustvelocity. The DC electrical power coming from a solar or nuclear power sourcehas to be converted to radiofrequency (RF) power, which is then absorbed by theplasma. The fraction of the RF power that is converted to thrust is called the“thruster efficiency”. Now we have demonstrated in the lab the 70% thrusterefficiency we need to achieve the 60% end-to-end system efficiency, at therequired exhaust speed.

Short for Variable Specific Impulse Magnetoplasma Rocket, VASIMR® is ahigh-power plasma-based space propulsion technology being developed by Ad Astrathat could provide far more efficient inspace transport than today’s chemicalrockets. The company envisions an initial space test of the technology in late2014, followed by commercial deployment shortly thereafter to greatly reducethe operational costs of maintaining an evolving space infrastructure,including space stations, satellites, lunar outposts and fuel depots in theEarth-Moon environment. Ultimately, VASIMR® engines could also greatly shortenrobotic and human transit times for missions to Mars and beyond.

http://www.adastrarocket.com/AdAstra%20Release%2023Nov2010final.pdf