Angela Des Jardins never actually saw the alleged Chinese spy balloon when it made an appearance over Montana earlier this month.
"It was over Billings, which is a couple hours east of here," says Des Jardins, a physicist at Montana State University in Bozeman.
But she's seen plenty of others. Physics and engineering students at Montana State and all over the country use balloons for experiments and to test things they've built. Student teams from the Nationwide Eclipse Ballooning Project, for example, have have big plans for doing research during next year's total solar eclipse.
In the past, student balloon launches have been festive affairs. But in a world where every balloon is a suspected foreign agent, what will people do when they see a white orb rising from a field?
"Are they going to bring a gun and try to shoot down the balloon?," she wonders.
Des Jardins is one of many scientific researchers around the country who have, until now, been using balloons under the public's radar. Balloons regularly carry physics experiments, collect atmospheric data, and test new pieces of scientific equipment. It remains to be seen whether that research will be disrupted following the Chinese balloon furor, but many scientists involved with the work are bracing for change.
"I'm just hoping that the response isn't painted with such a broad brush that it doesn't impact these other programs that are vital and important to the U.S.," says Gregory Guzik, a professor at Louisiana State University who works with high-altitude balloons.
It already appears that at least some innocent balloons have been blown out of the sky. President Biden said late last week that three objects shot down over the U.S. and Canada were likely "tied to private companies, recreation, or research institutions studying weather or conducting other scientific research."
One of those balloons is now suspected to have been a hobbyist balloon that had circled the earth six times before it was likely brought down by an AIM-9X sidewinder missile over Canada's Yukon Territory on Feb. 11. The balloon, K9YO-15, was built by the Northern Illinois Bottlecap Balloon Brigade, and was being tracked by amateurs when it wandered into airspace monitored by the North American Aerospace Defense Command.
"We knew the moment that the intercept was reported, whose it was and which one it was," Dan Bowen, a stratospheric balloon consultant, told NPR.
Balloons are also used for weather forecasting and commercial ventures. There are no firm numbers on how many civilian balloons are aloft at any given moment, but they're a constant presence in the skies above America. Small balloons like those used by Des Jardins' students drift far above the operating height of aircraft, into the stratosphere.
"Up that high, it's almost like the vacuum of space — it's cold, so you can test a lot of things and give budding engineers and scientists the experience," she says.
The objects typically rise until the pressure difference between the balloon and the thin atmosphere causes them to pop. Then parachutes carry their payloads back to earth, where students retrieve their work. The flights last a matter of hours, instead of days or weeks.
Other, larger balloons can carry payloads that are thousands of pounds. Guzik says they've been used to study everything from solar activity, to cosmic rays and the ozone layer.
Guzik works regularly with large scientific balloons that closely resemble the Chinese spy balloon in appearance. He says he is not particularly worried that his balloons will meet a similar fate. They carry radio beacons that let everyone know they're not a threat.
"All of our balloons have transponders. We know where they are," he says. That allows researchers to contact officials at the Federal Aviation Administration or other agencies who might need to know.
In general, "balloon researchers are careful to follow airspace and other government regulations," says Joan Alexander, a senior scientist with NorthWest Research Associates, a scientific research organization that regularly works on balloon campaigns. "Our research balloons carry no surveillance capability, and safety is always a primary concern."
But Guzik is worried that the Chinese balloon may increase the regulation governing high altitude balloons, making it harder for scientists to do their work. For example, his balloons usually launch from a town in New Mexico near a sensitive government facility:
"While we don't try, we do brush up against the White Sands Missile Test Range," Guzik says.
In the past, it hasn't been a big deal if a balloon drifts near — they simply notify White Sands, and the balloon bobs by, at an altitude far above airplanes and other flying projectiles that might cause concern. But Guzik worries that fears about spying could change the rules, making it harder for peaceful balloons to fly. He can imagine airports, military bases, and many other facilities trying to restrict balloon overflights, something that can be difficult to do, since balloons tend to blow with the wind.
He says right now the conversation is too focused on the military threat from balloons.
"This other side of the story, the useful, practical ballooning that helps students, helps technology and our better understanding of the Universe, really needs to get out there," he says.