Aiming sky high in global balloon challenge
A team of Stanford students did something they think no one ever has before -- take a photograph of a high-altitude balloon from one even higher. And that might be enough to come out on top in the Global Space Balloon Challenge.
PATTERSON, Calif.--"You ready to launch some balloons," Kyana Van Houten called out in a singsong voice.
It's 5:20 a.m. on Saturday, April 19 and Van Houten, an energetic 19-year-old with shoulder-length brown hair, is bouncing on the pavement outside the Days Inn, the kind of interstate highway motel where a Friday night room with a king-sized bed costs $57. With tax.
Van Houten and nine fellow Stanford students had descended on California's Central Valley to compete in the Global Space Balloon Challenge, a worldwide celebration of high-altitude ballooning.
And these kids -- the oldest is 23 -- hope they have a prize-winner on their hands. No matter what, though, they're promoting their passion. "One of the biggest reasons we created [the challenge]," said Van Houten, who had worked alongside the competition's founders, "was to foster a sense of community across everyone involved with high-altitude balloons across the world."
The Stanford students won't find out if they beat out the dozen of other teams from around the world until mid-May when the winners are announced for: highest altitude, best design, best experiment, and best photograph. The prizes are bragging rights in the high-altitude balloon community.
Started by Stanford, MIT, and the University of Michigan, the challenge, according to the competition's official Web site, is about encouraging "people of all ages to get their hands dirty building their own space hardware, and to promote the spirit of hardware hacking and international [science, technology, engineering, and mathematics] collaboration."
The Stanford team is planning two launches -- one that could go as high as 140,000 feet to vie for the high altitude crown. But their hearts are really set on winning the best photograph title, and they've got just the concept to succeed. The only problem: It's never been tried before, and any of half a dozen things could foil their chances.
A global team
Just before sunrise, the team arrived at a big grassy field riddled with gopher holes and littered with dried cow dung. Almost immediately, they jumped into action, gathering dozens of individual components and assembling them carefully. Multi-page checklists on clipboards govern every step.
It starts with hauling huge tanks of hydrogen off the back of a white Ford F-150 4x4. Helium used to be the gas of choice for high-altitude ballooning, but a global shortage has led to skyrocketing prices. So hydrogen it is. It doesn't matter that much expect that the mass is different, Robbie Karol, a 23-year-old masters student in aeronautics and astronautics, tells me.
While most of the team is 20 or younger, with fewer than three launches under their belts, they radiate confidence. Each are members of Stanford's Student Space Initiative, whose alumni are starting to work at companies like SpaceX. They have the kind of multi-national backgrounds expected from a bunch of Stanford physics, electrical engineering, and mechanical engineering majors. There's a Russian, a Pole, a Turk, a Persian who grew up in China, and a few Americans.
Best photograph
For these space geeks, the main event is the second launch of the day. The goal? Launching a system with two latex balloons, one higher than the other, so they can take a picture showing the lower balloon, the horizon, and space, in a 120-degree field of view. This is the tricky part because no one has ever done it before. "We decided what picture we wanted first, and then figured out how to accomplish it," added Logan Herrera, a 19-year-old from North Carolina,
The design involves a delicate system with two 1,200-gram balloons separated by a 25-foot-long lightweight carbon fiber rod. One of the balloons is at the end of a longer rope so that it rises well above the other. Underneath hangs a Styrofoam box packed with the payload: a pinhole camera, a 900 Mhz radio, a PC board loaded with sensors, a Spot GPS, a pressure sensor, and even a hand-warmer to keep the contents a little warm once the balloon reaches the freezing temperatures at high altitude.
To get the dream picture, the balloon has to get high enough to have both space and the horizon in the frame. Yet the biggest obstacle is keeping the whole system stable once it takes to the air. If for some reason the rod doesn't stay flat, the camera may move out of position -- and miss the shot.
'OK, let's launch'
The earlier high-altitude launch hadn't gone quite as planned. Though the team's design reached 110,000 feet, there were unanticipated problems the moment it left the ground. A two-balloon system in which one with more hydrogen lifted a second one with less gas, the design faltered the instant it took off . The lower balloon inverted like a cup, causing significant drag and cutting the anticipated rate of ascent in half, to about 500 feet a minute. That meant a far slower rise into the sky than expected.
By 12:40 p.m., it was time for the best photograph launch. The team went over every detail, trying to shave even a hundred extra grams off the launch weight before deciding instead to even out the two balloons' mass by adding a little more rope to one. Finally, they were ready. "OK, let's launch," said Aria Tedjarati, who along with Van Houten, helped organize the team. "What are we waiting for?"
It felt very like the famous moment when astronaut Alan Shephard, tired of waiting for the launch of his Mercury rocket, yelled, "Let's light this candle."
Just minutes later, the balloons were set loose. Rising quickly at 700 feet a minute, they were soon just a speck in the sky. As one, the team watched, at first horrified that it might have become destabilized, and then exulting when they realized it was just an optical illusion. Everything was perfectly aligned.
And their photo scheme worked. After recovering the balloons a few hours later at a field two hours southeast of Patterson, the group examined its imagery. There it was, the shot they'd been imagining for weeks: the lower balloon sticking straight up, the Central Valley far below, a cloudy horizon in the background, and the darkness of space above.
"There were times when we doubted that this design would work," Van Houten said later by phone. "When we finally let go of it, and could see it was retaining its stability, and wasn't being knocked over, that was amazing."