“Balloon payloads can now weigh less and so the balloons can be smaller, cheaper and easier to launch” than satellites, Layton said.
Blake Herzinger, an expert in Indo-Pacific defense policy at the American Enterprise Institute, said despite their slow speeds, balloons aren’t always easy to spot.
“They’re very low signature and low-to-zero emission, so hard to pick up with traditional situational awareness or surveillance technology,” Herzinger said.
And balloons can do some things that satellites can’t.
“Space-based systems are just as good but they are more predictable in their orbital dynamics,” Layton said.
“An advantage of balloons is that they can be steered using onboard computers to take advantage of winds and they can go up and down to a limited degree. This means they can loiter to a limited extent.
“A satellite can’t loiter and so many are needed to criss-cross an area of interest to maintain surveillance,” he said.
What might it be spying on?
According to Layton, the suspected Chinese balloon is likely collecting information on US communication systems and radars.
“Some of these systems use extremely high frequencies that are short range, can be absorbed by the atmosphere and being line-of-sight are very directional. It’s possible a balloon might be a better collection platform for such specific technical collection than a satellite,” he said.
Retired US Air Force Col. Cedric Leighton, a CNN military analyst, echoed those thoughts.
“They could be scooping up signals intelligence, in other words, they’re looking at our cell phone traffic, our radio traffic,” Leighton told CNN’s Erin Burnett.
Intelligence data collected by the balloon could be relayed in real time via a satellite link back to China, Layton said.
Analysts also noted that Montana and nearby states are home to US intercontinental ballistic missile silos and strategic bomber bases.
