The reasons to plunge into an unknown farmer’s cornfield in central Illinois in the middle of the night are not innumerable.
1. You really want some corn, and you’ve heard it’s better toward the center.
2. You are in a Stephen King novel, and it’s not looking too good for your character.
3. Your ball or other significant object has ended up in said field, and you’ve got to go get it.
It was the last reason that had me and a squad of Adler Planetarium science interns and volunteers taking the maize plunge one very early morning this summer.
We had flashlights, of course. We had GPS coordinates for the item we were seeking. We had a second radio device that was supposed to get louder as it got closer to the wayward thing. And we all had highway safety vests, just to make it clear we weren’t animals in need of being shot.
But still. Our target was the payload to a high-altitude balloon that, not too many minutes before, had been cruising over Kankakee, literally in the stratosphere.
The latex balloon, about the size of a car when it was launched from a park near the Kankakee River, had grown as a big as a house before it finally burst up there at the boundary to space. But the payload, the balloon’s “basket” stocked with cameras and scientific instruments, was no bigger than a compact microwave.
While a needle in a haystack is profoundly insignificant, a microwave in a cornfield is no sore thumb. And if you’ve ever experienced the disorientation of a corn maze, you’ll have an idea of how much worse it can be in a field of the crop with no pathways cut through it.
The attempted retrieval was to be the end of a test mission, part of an overall project dubbed Nitelite, that could break new ground from so high up in the sky. The Adler team is attempting to be the first — in the world, they say — to use high-altitude balloons to map the light pollution a city emits. The metropolis it has in mind, of course, is the one the planetarium calls home, Chicago, city of the big shoulders and the unceasing evening glow.
“We’re trying to prove you can get high-quality research data which is actually better than the data we get from satellites,” said Ken Walczak, project manager for Far Horizons, the Adler’s “hands-on science exploration program” that, for the past dozen years, has put its student and adult volunteer workers to the task of doing interesting things with high-altitude balloons.
Last year, the program used balloons to get a very different view of the solar eclipse. This year, said Walczak, “in a city filled with light pollution, we were thinking, ‘Well, what could we do that helps light pollution research?”
Mapping terrestrial light emissions has been done with images from satellites in orbit, of course. And it’s been done with airplanes. But that middle realm, with the balloons operating at about 80,000 feet, should provide a better perspective than a plane and more detail than a satellite. And it is so very much cheaper to pull off than the other two options, assuming the not-insignificant engineering challenges can be solved.
It can cost tens of thousands of dollars for an airplane flight to make a map of the light a city emits, Walczak said he has learned. “Our mission should cost less than $5,000,” he said.
It’s such a promising idea that, on the strength of its test missions alone, he said, the Nitelite crew has been asked to speak about their work this fall in Utah at ALAN 2018, “the 5th International Conference on Artificial Light at Night.”
Even without hearing about such a scientific gathering, you probably knew that light pollution is an increasingly front-burner issue. It affects the health of humans and animals in its vicinity, research says. It can cause migratory birds, which navigate by the light of the moon and stars, to lose their way. And it keeps urban dwellers — and those in their city’s vicinity — from seeing the stars and planets in the sky.
“I was an astronomy nut when I was a kid in northwest Indiana,” Walczak said. “You always knew, Look south. There’s no point in looking north because Chicago’s there.”
Meanwhile, Chicago is in the midst of replacing its hundreds of thousands of glowing, old high-pressure sodium lights with better focused, remote controllable LED ones. When the installation is complete by 2021, its electricity bill and nighttime brightness will have diminished, the city says, but some contend the reduction should be greater and that a different-than-specified light bulb should be used.
The Nitelite photos should help, by pointing out the difference between old bulbs and new and giving a better read on how significant it is.
So sometime in September, the Adler crew hopes to fly one of these balloons over Chicago, snapping enough photographs to produce this first-of-its-kind light map of the city.
Those images will have good enough resolution, said Walczak, to be able to “capture every single streetlight.”
But first there are some problems to solve, problems that reared their heads during the Kankakee-area voyage after several successful previous tests. One is getting the on-board camera and computer that controls it to keep contact with each other during the flight. That contact is essential for being able to stitch together the images into an accurate light map.
Another, also big one is to control the balloon’s flight so that it will level off at about 80,000 feet; this is significant because, instead of continuing its ascent until the balloon pops farther up, it will be able coast across the city in the prevailing upper-atmosphere winds to provide a stable photographic platform.
The test flights take place downstate because in less densely trafficked areas there is no need for the FAA approval that will be required to cross Chicago, Walczak said.
So early in the July evening, almost five hours before entering the cornfield, we pulled into a Kankakee River State Park parking lot northwest of Bourbonnais. That it was the lot for the park’s archery range, and we were going to be launching a balloon, perhaps should have given us pause.
But no archers were present as the day’s light disappeared. One crew laid out a tarp across the parking lot and began to prepare the helium tanks to inflate the latex balloon — which feels like nothing so much as a hospital glove or, no getting around it, a condom. This work was done in the beams of one of the Chicago teams’ car headlights.
Meanwhile, others got the payload ready. That meant a GoPro camera on one side; the main camera, an industrial grade CMOS imager, looking downward; and various beacons that would allow the earthbound scientists to track the flight as it ascended and the payload as it floated back to Earth with the help of the attached small parachute.
A team worked frantically, on laptops set up on a portable table by the side of a van, to get the computer control program working, but due to an apparent issue with the power source, it kept rebooting, a very bad sign.
“If it doesn’t go the first time, it’s not going to go,” said David Hurst, a volunteer and CEO of Chicago’s Orbital Transports, which does space logistics for small satellites, like the one Far Horizons is hoping to win NASA approval to launch in the future to do a different version of the light map.
“But it worked in the lab,” somebody said. And, indeed, it also worked on three previous test flights.
“This is both the joy and frustration of using consumer electronics,” said Jeremy Seeman, a University of Chicago grad student and another volunteer with the program, as he worked with Hurst on the computer issue. “They’re cheap. And they’re cheap.”
There are many high-tech elements to such a mission. But the power source in question was the kind of lithium ion battery you might carry around to give your cellphone an emergency charge, and it wasn’t supplying the steady power necessary.
Zip ties are more reliable and an indispensable part of the project. And the payload itself looks a little like a cooler whose owner isn’t prepared to buy a new one. It’s got the distinctive dull silver of duct tape atop its orange shell, holding things together. Duct tape was used, too, to help affix a tracking device to the parachute that would control the inevitable descent.
An earlier Adler balloon — Far Horizons has made more than 120 flights, only the last handful related to the Nitelite program — had handwriting on its side: “HARMLESS AMATEUR RADIO EQUIPMENT. ADLER PLANETARIUM,” and a phone number. The scientists didn’t want people to worry if they came across it in their own cornfield.
Walczak and the team weighed the payload and did some quick calculations to determine how much helium the balloon needed. They opened the tank valve to fill it, and he yelled over to where the payload was being prepared for flight:
“GoPro,” he said across the parking lot. “Has anybody started the GoPro?”
“Yeah, we just did it,” responded Seeman.
As Walczak waited, he stared across the road to the north. “So you look in that direction, you see the glow?” he asked. “That’s not sunset. That’s Chicago.”
And then the payload was ready and strung to the balloon. Someone said, “5, 4, 3, 2, 1. Go!” And it went upward and a little to the east, not quite like a rocket but quick enough that it was out of view in seconds.
As the balloon soared heavenward, the team climbed into its vehicles and started driving, able to track the balloon’s progress via a website its instruments communicated with. At 62,000 feet, Walczak said, “Hey, we’re above patrolled airspace.”
And as it soared above 90,000 feet without slowing, it became apparent that the module that was supposed to level off the flight hadn’t worked. The balloon was going to climb until it burst.
A subsequent flight had problems with the leveling device and the imaging system as well, but Walczak said he thinks the Far Horizon team has been able to solve those issues in the lab. His plan is to run a few more quick missions downstate, testing the leveling system only, in hopes of doing the actual light-mapping flight over Chicago by late September or October.
“This is what’s funny about the whole business of doing something new,” he would say later. “It’s one of those two-steps-forward-one-step-back kind of things. … It’s why you always put the duct tape in the spacecraft.”
Over tacos at a fast-food restaurant in Bradley, the team kept tabs on the flight. And then it was time to get back in the vehicles and start, essentially, chasing it to wherever it would choose to land. Somewhere above 100,000 feet, the flight profile made it clear the balloon had popped, and the descent, even with the small parachute deployed, was rapid.
Worst-case scenario, the equipment would come down in the Iroquois River or high up in a tree. Best case would be on a roadside or in a field of low-slung soy beans. Both seemed possible at points during the chase.
“It’s due west of us right now,” said Walczak. “But 12,000 feet is over two miles up.”
We stopped the cars and got out to scan the horizon, looking for a chute, for the blinking light. What was that? Nope, airplane.
“I see a blink, straight up,” someone announced.
“Oh, I see it!”
It kept coming down as all around us was the medium-case landing scenario, row after row of corn plants taller than the tallest NBA player. In there, nearly a quarter-mile from the road, the payload’s signal told us it had returned to Earth.
The junior members of the crew strapped on the retrieval gear, the vests and the flashlights, grabbed the homing device and a walkie-talkie and entered into this meeting with big agriculture.
Three hundred yards on an open country road is nothing. But that distance through cornstalks, wondering if you’ve overshot your target, seems eternal.
We followed one row that went perpendicular to the road for most of the distance, keeping hands up high to push the leaves aside. Then, when GPS told us it was time to go to the right for another 20 yards or so, we did that.
Suddenly, in the beam of my headlamp, there was something on the ground that was neither dirt nor vegetation. It was a little orange box striped with silver.
“There it is!” I said.
The box had lines running from it to a red sheet, the parachute, higher up in the corn.
“Hey,” Seeman said into the walkie-talkie back to Walczak and Hurst waiting by the vehicles, “we got the payload! We are un-zip-tying it now, and we’ll be back shortly.”
One by one, we squeezed back out of the corn and onto the roadside with relief. A big part of science is field work, but this was taking the phrase almost too literally.
sajohnson@chicagotribune.com
Twitter @StevenKJohnson
