Road to Mars: JPL scientists prepare for a supersonic test over Hawaii


If the wind blows the right way, sometime around sunset on Friday night, three tractor tugboats operated by P&R Water Taxi will pull up anchor in Honolulu and set off for the aquamarine waters west of Kauai.

On Saturday, assuming all goes well, these vessels will collect the sodden remains of a massive high-altitude balloon, a saucer-shaped spaceship and its black box (which is designed to detach when it hits the water in case the vehicle starts to sink).

If they do, it will mean the first full-scale test of NASA’s new Low-Density Supersonic Decelerator (or LDSD) took place high in the atmosphere. The LDSD could be the space agency’s next hero in the quest to explore the Red Planet; the device acts like a brake pedal for large loads headed to its surface.


“This is part one of a 12-step program to get people to Mars,” said Project Manager Mark Adler of NASA’s Jet Propulsion Laboratory in La Canada Flintridge.

Right now, step one is still in progress. The scientists are in Hawaii to test whether they can even create the right conditions to test the vehicle for Mars.

NASA experts picked Hawaii as their test spot because winds at the tropical paradise are ideal for launching the device away from people, high into the stratosphere, where atmospheric conditions are about as close to those on Mars as they can find on Earth. (Their only other good option was in the Australian outback, but the logistics of schlepping people and gear into a remote desert made Hawaii the simpler option.)

The tugboats are just the opening act of a long and intricate drama that will play out the night before LDSD’s launch at the Pacific Missile Range Facility.

“It’s like baking,” said Grace Tan-Wang, the operations lead on the project. “You have all your ingredients out there, but actually mixing it all together, that has to happen the day of.”

Different teams will report to work at different times and begin readying their portion of the project. Nine hours before launch, the balloon specialists will assemble the launch tower and rally the helium trucks. Vehicle engineers will begin rolling the LDSD toward the launch pad, which lies a mile from the storage hangar along the main road of the Navy base on the flat, fertile soils of the Mana coastal plain.


Once the test craft arrives at the launch site, crews will strip off the vehicle’s storage covers and connect the umbilical cords linking it to the balloon that will hoist it into the sky and to the data loggers that will record every aspect of its short supersonic flight.

Eight hours before launch, the operations team, including Tan-Wang, will file into the team’s command center. They will start up the vehicle’s operation and communication systems, running through checklists and making sure it talks to the arrays of antennas perched high in the rugged hills behind the base.

With four hours to go, Adler will take his position in the base’s high-security command center, known as the ROCC for Range Operations Command Center. From here, he will give the go-ahead for each major step of the process -- assuming the range staff, who wield absolute control over the base and its missions, approve.

Robert Manning, the chief engineer, will be there too.

“We all hope he has nothing to say,” Tan-Wang said, “because he’s only there to deal with unexpected events.”

Manning knows this is true: “I specialize in failure,” he said. “And I have to admit it’s a lot of fun.”

That basically sums up Team LDSD’s approach to the never-ending circus of obstacles and setbacks inherent in developing new technology: revel in them.


“We learn even more when we fail,” Manning said, echoing a sentiment also expressed by Adler and every other member of the team. Adler likes to juggle in his spare time, and invokes a saying he heard when he was just starting out, “if you’re not dropping balls, you’re not learning how to juggle.”

So far, the team has learned a lot about how to launch and test a vehicle designed for Mars while it’s still stuck on Earth. (All of this would be much easier, Manning noted, if they could just test the vehicle on Mars, where it belongs.)

The NASA team figured out how to install a rocket engine in the prime real estate where the parachute usually belongs, smack dab in the center of a circular projectile. They have learned new knots for attaching the device to the balloon and debated which type of dye markers will help them find the floating objects in the sea.

But they won’t know until the test goes off which — if any — of the mistakes they’ve unknowingly made will help prepare them for Mars.

Manning explained that there are very good reasons to hope for mistakes in Hawaii.

“There’s failure, and then there’s failure,” he said. The first kind has a happy ending; the second is devastating, sometimes costing billions of dollars and years of work.

The wildly successful Spirit and Opportunity rovers were made possible in part by the dismal fates of Mars Climate Orbiter, which never hit its target because of a metric-to-English unit mistake buried in its code, and the lost Mars Polar Lander.


With old-fashioned human error, “the mistake is not making the mistake, it’s not catching it,” Manning said.

The point of testing the LDSD is to root out these problems now, to scrub out any chance of real failure. That leaves only one other source of problems: the ones they can’t predict.

“What we fear most is ourselves,” Manning said. “Our failure of imagination.”

They will find out soon if they dreamt up all the possible ways things could go wrong.

The five-day launch window opens Saturday, and staff meteorologists have started keeping a close eye on weather conditions. The long-range forecast calls for favorable winds, and the team is preparing to get that late-night call. (If not, the tests get shelved until next year.)

“The team is anxious,” Tan-Wang said. “We’re all like, ‘Let’s do it!’”

For all things science, follow me at @ScienceJulia.