My alien body produces heat like yours produces carbon dioxide. I can't control it; it's not a conscious thing. Where I come from it's not unnatural. We use ourselves as energy sources. That's one of the reasons you will never be able to stop us. We aren't going to blow your planet up. We're just going to start landing in ships fueled by our own body heat. You cant shoot us because your primitive projectile weapons will incinerate before they ever reach us. There is nothing you can do, except watch and wait as we melt your polar ice caps in a matter of hours and flood your entire planet. Then we'll leave you to drown. We have our own planet, thanks.