Of the 13 low-cost CubeSats launched on a Minotaur-1 rocket last November, fewer than half of them were ever heard from again. What went wrong?
Adam Kemp, a teacher at the Thomas Jefferson High School for Science and Technology in Alexandria, Virginia, whose students became the youngest team ever to send a satellite into space, thinks maybe their CubeSat sat idle for too long in the NASA-provided Minotaur during last year’s government shutdown. Or maybe the rocket flew through some sort of high-radiation zone after the launch.
“To be honest, we have no idea,” says Michael Swartwout, assistant professor at St. Louis University and principal investigator for the school’s COPPER CubeSat, which successfully deployed from the Minotaur into orbit, but then never responded to communications from St. Louis. “Our best guess is that it was an unfortunate combination of factors, such as the antennas failing to deploy on time, leading to the solar panels being blocked and the battery draining beyond the point of recovery.”
COPPER and most of its co-passengers were their builders’ first spacecraft, meaning they had only a 50/50 chance of success. That’s according to Swartwout’s research, which includes tracking how universities are faring in the satellite revolution brought on by the advent of the cheap, standardized CubeSats. The first time out is always the hardest, he says. Schools that go on to launch a second or third CubeSat tend to do better, succeeding 75 to 80 percent of the time.
Still, “with 8 of 13 not working,” says Swartwout, “you ask the question whether we were unlucky or whether we were all missing something.”
Despite the long list of tests NASA has recommended for student-built satellites, basic failures appear to be common among Cubesat first-timers. Swartwout thinks it’s a combination of two factors: the first is that many universities jumping on the Cubesat bandwagon are bringing very little if any experience to the task, so there’s a steep learning curve. Second, sending a working spacecraft into orbit is harder than any newbie thinks it’s going to be, so students tend to run behind schedule and rush the critical tests that ensure their Cubesats will work unattended in space. They might cut back on testing all the elements together as a system, for example. Or maybe they skip the step of letting the Cubesat run continuously for a week, powered only by a bright lamp to simulate sunlight, the way it would in orbit.
Losing a Cubesat can be a learning experience, however. Despite the disappointment, says Swartwout, having a bona fide space failure under their belts benefits students after they graduate. “Companies love it because the students are making the mistake on our dime and not on theirs,” he says. “The victory here is that students are experiencing the complete mission lifecycle, and they can take that knowledge, success and failure, and use that professionally in ways they couldn’t before.”
Next time the St. Louis students send something to space—their Argus and Rascal Cubesats are already in NASA’s launch queue—they’ll have a great advantage. This time they’ll be veterans.