Once we’ve demonstrated a 200-kilowatt prototype engine operating at full power on the ground, the next step is testing an identical version in space. We’re already testing the prototype unit in our vacuum chamber here in Houston, and we’re designing the actual flight engine, which is called the VF-200. We signed an agreement with NASA last December to actually mount the VF-200 on the International Space Station in 2012 or 2013. Unfortunately, the space station doesn’t have 200 kilowatts to give us. So what we’ll do is use the solar arrays of the station to charge a battery pack that we’ll carry on board, which will allow us to fire the rocket at 200 kilowatts for up to 15 minutes. We’ll do this again and again for months to qualify the engine in space. In 2013 or 2014, we’ll make clusters of 200-kilowatt engines to give us something close to a megawatt of electricity, and deploy them with a very high-powered solar array. This will be a robotic reusable “space tug” that can refuel or reposition satellites, or even send packages to the Moon at a much lower price. By charging for those services, we hope to bootstrap our way into developing a megawatt-class rocket. That rocket would be too powerful to test on the ISS, but it could perhaps be tested on the surface of the Moon where solar power is abundant. Like the ISS tests, we’d fire the megawatt-class VASIMR continuously for a period of one month, then two months, to validate and verify that it could be used on a human mission to Mars.
Once we have this capability, Mars isn’t really the only place that we can go. With a megawatt-class VASIMR, basically we will have access to the entire solar system. Mars is an interesting place, but so are Europa and Ganymede and Enceladus and Titan. These are places where we might find extraterrestrial life. Even with the 200-kilowatt solar-powered VASIMR we could do amazing things. We’re developing a concept to drive it close to the Sun, between Venus and Mercury, where it can get a momentum boost and catapult a probe into the outer solar system at high speed. This would let us deliver a package to Jupiter in one-and-a-half years; otherwise that trip takes about six.
One thing we’d like to do is maintain the ISS in orbit. The ISS has to be reboosted every few months; otherwise it gradually falls and burns up in the atmosphere. These reboosts require about 7 metric tons of rocket fuel per year. How much does it cost to get 7 metric tons of rocket fuel into orbit? $140 million. That’s the bill someone has to pay, each year, just for hauling up the fuel. The 200-kilowatt solar-powered VASIMR can do the same thing with about 320 kilograms of argon gas per year, which still costs about $7 million, but it decreases the price by a factor of 20. Of course, we have to make a little money ourselves, so the price decrease won’t be quite that large, but it can still save NASA a lot of money and net us a handy profit.
We would hope that, if not the US, maybe the Europeans, the Chinese, the Russians, or somebody else will develop a nuclear-electric power capability that we can marry up to this rocket. We have to realize that the US is no longer the only player. The US may choose not to do this, but that doesn’t mean the rest of the world will follow—not anymore. We no longer live in a confrontational world like the one that fueled the Apollo program in the 1960s. We live in a world that has to cooperate, to collaborate. The US has a tremendous opportunity to still be the leader here, but if it isn’t, others will be. Information is traveling faster everywhere now; technology has gained a foothold and developed in the nooks and crannies of the planet. The world has changed, and the US no longer has a monopoly on knowledge. We need to collaborate to build a capable space infrastructure so that we can truly explore.