The mass extinction event caused by the impact of an asteroid at the end of the Cretaceous age that wiped out 75% of life on Earth is widely accepted
Sorry, Bruce Willis...
"A more exotic scenario is that 'Oumuamua' may be a fully operational probe sent intentionally to Earth vicinity by an alien civilization"
The Japan Aerospace Exploration Agency posted the latest photos on its website
But, Hayabusa2 isn't the only asteroid-sampling mission operating right now
In 2013, an asteroid over 50 feet across and weighing some 10,000 metric tons slammed into Russia, unexpectedly
The odds of Earth being struck by an asteroid are remote, but the effects of such collision can range up to a planetary catastrophe
The space rock flying by Thursday is thought to be a dead comet as big as the Burj khalifa
Some missions might even need to be launched a year before impact