[KotOD]

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Serious discussion today folks. Your options are

Mass terrorist attack/nukes
Global warming
Gigantic natural disaster ie massive earthquake/meteor/hurricane
Sun Burns out
Alien attack
Other

Please discuss which option you think it most likely to end our planet.

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The Yellowstone Caldera is the biggest near-term threat to life, though it's unlikely to extinguish all life.

The biggest extinction threat medium-term is robots.

The biggest long-term threat is a close proximity supernova.