Balloon hobbyists, meanwhile, are also worried for other reasons — that the small balloons they launch into the sky could be shot down or that the focus on balloons could lead to tight restrictions on their little-known hobby.

Speculation has grown about whether one of the unidentified objects taken down by a US F-22 on Feb. 11 over Canada’s Yukon Territory was a small party-style balloon launched by a hobby group whose name is a whimsical reference to the children’s film “Up.”

The Northern Illinois Bottlecap Balloon Brigade recently said one of its balloons went “missing in action” on Feb. 11, near an island off the coast of Alaska. Then questions emerged after Aviation Week reported that, based on the last-known location and forecasting models, the balloon was predicted to have been floating over the Yukon on the day the F-22 shot down a mysterious object. Politico has also reported that the FBI spoke with the group.

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The Illinois-based group launches hydrogen-filled balloons that have GPS tracking and antennas, and can rise up to 47,000 feet, according to its website. It has not linked the fate of its missing balloon, which it launched months ago, to the shoot-down in Canadian airspace, and did not respond to a request for comment Thursday.

Many balloons are probably soaring overhead at any given moment, for purposes from weather monitoring to gathering intelligence, but hobbyists worldwide also launch balloons into the sky, including small ones referred to as “pico balloons.”

Balloon hobbyists have said it was possible the object was blown to smithereens by an F-22 was a GPS-tracked party balloon.

People launch balloons for radio experiments, or as part of projects to learn more about technology, balloons and the sky — as well as for fun, according to Dave Akerman, a member of the UK High Altitude Society who has launched nearly 100 larger latex balloons . Now enthusiasts are concerned “there will be a knee-jerk reaction to what happened,” he said in an interview.

He said he hoped that authorities and hobbyists could coordinate on reasonable guidelines or rules if needed. “It’s also in the interests of authorities not to be shooting down party balloons with missiles.”

While the evidence remains circumstantial in the case of the incident over Yukon, “what they described sounds exactly like these pico balloons,” he added.

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“The plastic balloons will stay up for several months, during which time they’ll circumnavigate the globe and then eventually the wind and weather get to them,” he said. While it depends on the size and weight, the small, light balloons typically don’t require permission from authorities for launching, he added.

President Biden has sought to convince Americans that the three objects shot down last week, after the Chinese balloon, did not appear linked to foreign surveillance programs. He said Thursday that intelligence officials thought “these objects were most likely to tie balloons to private companies, recreation or research institutions studying weather or conducting other scientific research.”

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US officials have yet to recover remnants of the object shot in Canadian skies, after the Pentagon chief said it was “absolutely important” to recover debris. The Royal Canadian Mounted Police said Thursday that while search efforts continued, conditions were “extremely challenging” in the varied terrain and harsh winter weather.

The Pentagon said it had no updates to provide as of Friday morning. The FBI could not be reached for comment late Thursday.

The detection of the Chinese balloon has also prompted the US military, which usually looks for threats such as missiles, to adjust its radar filters to detect smaller or slower objects that would normally be filtered out. That could partly answer why other objects were later identified in quick succession.

Helier Cheung, Dan Lamothe and Pranshu Verma contributed to this report.