Unknown flying objects can contain very highly toxic material.

There is one thing that you should not do with unidentified flying objects. Don't shoot them. In this text. All objects whose origin is unknown are unidentified. There is a possibility that things like spy balloons carry RTG (Radio Thermal Generator) or plutonium batteries. 

And if the shell of this thing is damaged radioactive material spreads to the ground. Things like radioactive materials can cause pollution and dangerous radioactive dose. Also, microchips can contain poisonous materials. 

There is also the possibility that the spy balloon has some kind of self-destruction system. That means if unauthorized people open the gondola. That thing detonates the self-destruction explosive. Also, the operation is dangerous for evidence like fingerprints and DNA samples that researchers can find from those balloons. 

But there is a small possibility. That the system that was shot down is some kind of alien device. And in that case, there is a possibility that things like antimatter tanks start to leak. That causes large destruction. 

The fact is that. If the origin of the balloon is unknown, that makes it unknown. Its purpose is unknown. When we see a balloon of unknown origin we can risk many things if we try to shoot it down. Maybe the balloon looks sweet and nice. But there is the possibility that some of those balloons use nuclear batteries. 

And that makes them dangerous. In some countries, the military has the right to make any kind of recon system that they need without caring about results. And the thing is that those balloons can be dangerous even if their origin is on civil bases. 

If the balloon collects samples from a higher atmosphere. That means there is a vacuum in the chambers. And that kind of vacuum can cause injuries. In the same way, their batteries can have very high voltage. And that thing can cause electric shocks. 

https://bigthink.com/starts-with-a-bang/shoot-spy-balloon/

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