7. A solar superflare would destroy the ozone layer
basically, it is a huge solar flare that probably hasn’t happened in our Solar System. But we have observed stars that have weaker magnetic fields than the Sun that exhibit superflares. The largest solar flare that we have recorded was the carrington event. It happened in 1859 and was so strong, it could be seen with the naked eye and even set telegraph systems on fire.
That was only 1/10,000 the energy of the largest known superflares. If one were to happen, the effects are pretty grim.
- airline passengers would receive high-doses of radiation
- all satellites would be damaged, but probably broken
- the ozone layer would be fucked
- loss of most radio communications
- and for a strong one, the Sun’s luminosity increase could cause ice to melt as far as the moons of Jupiter.” — intersecting_lines
8. Astroids hit the planet a lot more than you realize
“Many people don’t realize how relatively common asteroids entering our atmosphere are. I’m talking about 0.1 – 1000’s of kiloton explosions. Dozens each year. Most explode high up in the atmosphere and are harmless. Some explode a bit lower and shatter windows (remember Chelyabinsk)
And once in a while there is an event like the Tunguska event which leveled 2000 km² of forest.
Imagine something like that happening in a modern metropole.
And we have no way of stopping it.” — Bananedraad