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It's just a matter of time until an asteroid sets course for the earth. Our only hope of prevention? High-tech computers, satellites, and rockets.
Tornadoes can devastate entire regions within just a few minutes. They destroy anything in their path and their emergence is virtually unpredictable.
Humans are releasing CO2 and methane that's causing Earth's ice to melt rapidly. Can we stop ice from melting before its catastrophic consequences?