Since nobody has answered your question: I assume that China simply sent a balloon to spy on the US. Why a balloon? Because it's much closer to earth than a sat

Since nobody has answered your question: I assume that China simply sent a balloon to spy on the US. Why a balloon? Because it's much closer to earth than a satellite and can carry a heavier payload. And why they were not worried if it would be detected? Well, according to the Pentagon, China has sent several balloons over the US in recent years and nobody made a fuss about it until now.