In the silent vacuum of space, five autonomous robots churn through the lunar surface, digging up a loose layer of rock and dust and leaving rows of uniform tracks in their wake. Stopping only to recharge at a central solar power station, the car-sized machines process the lunar dirt internally to extract a type of helium so rare on Earth that a palm-sized container is estimated to be worth millions.
Discovered in December 2024, asteroid 2024 YR4 was briefly considered the most dangerous asteroid in decades after scientists initially estimated it had a 3.1% chance of colliding with the Earth in 2032. Closer observations quickly ruled out a city killer scenario, but instead astronomers calculated there was a 4.3% chance that the moon lay in the path of impact.
We found that life is more likely to survive an asteroid impact, so it's definitely still a real possibility that life on Earth could have come from Mars. Maybe we're Martians! The idea that life could have spread through the solar system or even the universe on rocks is known as the lithopanspermia hypothesis.
Plenty of asteroids can survive their fiery plunge through the Earth's atmosphere. If they're big enough, they can prove incredibly destructive, like the 60-foot Chelyabinsk meteor that exploded over the southern Ural region in Russia in 2013, releasing a blast equivalent to 30 times the energy of the atomic bomb that was dropped on Hiroshima. And in case an even larger space rock were to ever threaten humanity, we'd have to get creative to keep it from colliding with our planet.