In the meantime, Chang Díaz doesn’t need nuclear power to continue the development of his singular engine. “We will deploy VASIMR as a solar-powered rocket that can engage in a number of important near-Earth activities,” he says.
VASIMR’s first test in space is tentatively set for 2016 aboard the International Space Station. Instead of nuclear power, the engine will rely on bursts of power from large battery packs charged by the station’s solar panels. Assuming all goes well, Chang Díaz says, Ad Astra will then pursue multiple near-term applications of VASIMR, such as periodically nudging the space station and other large satellites into stable orbits.
Chang Díaz also wants VASIMR, in its interim role, to become a “space tug” that could power the rockets that haul provisions to space stations and carry satellites to their designated orbits. In other words, he says, “we want to get into the trucking business.” His rocket could also serve as a garbage truck, getting dead satellites and discarded upper-rocket stages out of their dangerous orbits around our planet (a job the larger chemical-fueled rockets can’t perform efficiently because they use too much fuel).
Such intricate tasks, requiring about 200 kilowatts of power, are anything but make-work. “They will tell us what we need to know to build rocket engines that can handle megawatts of power,” says applied physicist Tim Glover, a board member and co-founder of Ad Astra. “It’s a step we can’t skip.”
When VASIMR’s engine technology matures and lighter nuclear reactors are ready for spaceflight, the time will come for people to move beyond Earth’s orbit, with Mars being the logical next stop. Chang Díaz regards a trip of this sort as more than just another adventure. The exploration of space, he says, is essential for the survival of humanity — the latest step in a process that’s been underway since early humans first began to search the world around them.
Eventually, humans will almost certainly venture deeper into the solar system, moving farther away from the pale blue dot we call home. As Chang Díaz sees it, “Mars is just the beginning.”