After ruling the Earth for over 160 million years, the dinosaurs finally met their fate, thanks to a visitor from outer space. About 66 million years ago, an asteroid that stretched at least 10 kilometers across the world of the dinosaurs caused a devastating blow, triggering earthquakes, tsunamis, volcanic eruptions and climatic disasters that quickly wiped out 75% of life.
Referred to the Giant Impact Hypothesis – a scientific theory which suggests that the Mars-sized planet Theia collided with Earth 4.5 billion years ago, sending a huge amount of rocky debris in space that eventually coalesced into our moon (Mars is about 4,200 miles long or 6,700 kilometers wide, more than 500 times the width of the dinosaur-killing asteroid).
Scientists speculate that Theia’s core and part of the mantle merged with ours, not to wipe out our planet, but to remain underfoot for eternity in the future where first life evolved. Experts disagree on whether this ancient collision was a head-on collision or just an obvious hit, but there’s no doubt that if there was life on Earth at the time, Theia would have destroyed it. (Scientists believe life may have originated 4.4 billion years ago, just a few million years after Theia’s impact.)
Death from above
As the mass extinction of non-avian dinosaurs shows, even if Earth itself still existed, it would take much less time than a rogue planet to seriously destroy life on Earth. Collision with a larger rock at least 1 kilometer wide would trigger a global climate catastrophe that “could lead to the end of civilization”, said astrophysicist Gerrit L Verschuur of Rhodes College in Memphis, Tennessee.
During this season of misery, so much dust and toxic gases can cloud the air that plants can no longer convert sunlight into energy through photosynthesis. Plant life will die out all over the world and animals will soon follow. Naturally, NASA and other space agencies take the threat of asteroid impacts very seriously and are keeping a close eye on thousands of potential impactors in our solar system. The good news is that there is no danger of any potentially dangerous asteroids hitting our planet for at least the next 100 years. On September 26, the space agency rammed an unmanned rocket into a 525-foot-wide (160 m) asteroid called Dimorphos, hoping to slightly alter the space rock’s trajectory.
