The $ 470-thousand worth AIM-9X Sidewinder missile missed and went into the great lake, while the second missile fired by the jet blew up the object, said Milley.
Most air platform has an engine that emits infrared (IR) emission. The Chinese balloons have no engine, but they have solar panels to charge batteries. These panels are the only infrared light source to be detected.
Raytheon’s AIM-9 Sidewinder is a short-range air-to-air missile. It uses infrared homing as a guidance system, and the proximity fuse detonates the warhead when it is near the air platform’s engine. Most Sidewinder-9 missiles are equipped with IR homing. Infrared homing is a passive weapon guidance system which uses the IR light emission from a target to track and follow. 
Sidewinder-9X has an IIR seeker to target air platforms with infrared images. This requires much more signal processing, but the missiles become more accurate. It should be noted that air-to-air missiles are designed to hit moving targets.
Most air platform has an engine that emits infrared (IR) emission. The Chinese balloons have no engine, but they have solar panels to charge batteries. These panels are the only infrared light source to be detected.Raytheon’s AIM-9 Sidewinder is a short-range air-to-air missile. It uses infrared homing as a guidance system, and the proximity fuse detonates the warhead when it is near the air platform’s engine. Most Sidewinder-9 missiles are equipped with IR homing. Infrared homing is a passive weapon guidance system which uses the IR light emission from a target to track and follow. Sidewinder-9X has an IIR seeker to target air platforms with infrared images. This requires much more signal processing, but the missiles become more accurate. It should be noted that air-to-air missiles are designed to hit moving targets.
