It’s been said that Earth exists in a massive cosmic shooting gallery as bits of ice and rock fly past the planet on a daily basis. Small asteroids are hitting the planet at all times, but on occasion, something considerably larger lines up a shot and Earth has a bad day. Around 65 million years ago there was one of those days when an object roughly six miles across hit the planet and caused the extinction of most land animals, including the dinosaurs.

When that impact happened, it would have ejected billions of tons of matter from the surface, and the question investigated by a new analysis out of Japan’s Kyoto Sangyo University is a simple one: what happened to all of it?

Researcher Tetsuya Hara calculated the most likely trajectory for all those Earth rocks, and found that a surprising amount of them would have ended up in unexpected places. The moon, being the closest celestial body of any size would have gotten a fair amount, as would Mars being further away, but more massive.

Due to the gravitational realities of the solar system, Jupiter’s moon Europa would have collected nearly as much Earth mass as the Moon. Because Jupiter itself is so massive, it would have swept up a large number of Earth rocks, allowing them to fall into orbit before colliding with its moons. Going a step further, Hara also calculated how much Earth material could have reached other stars.

The numbers indicate that given the right conditions, many tons of Earth asteroids could have arrived in solar systems up to 20 light years away (given a million years or so). The report goes on to get quite a bit more speculative, but also more interesting as it assesses the possibility that microbial life could survive that journey.

What we’re talking about here is the theory of panspermia, which states that life is regularly transported throughout the universe by asteroids and comets. Throughout history, panspermia has been considered unlikely for various reasons, and does still play a roll in various fringe pseudo-science claims. Conventional wisdom said that even hearty bacteria were too fragile to survive long in space, but more recent discoveries have to make you wonder.

An entire class of microorganisms called extremophiles (which is coincidentally what the ExtremeTech staff call each other) are capable of surviving in conditions of extreme cold, heat, acidity, and more. In fact, some extremophiles have been known to live entirely inside rocks here on Earth. So why not rocks in space?

Another option is that bacterial spores could end up stuck in space rocks ejected from Earth. Some species of bacteria can purge themselves of water, and generate a spore to keep the cell alive but dormant. Bacterial spores are highly resistant to heat, cold, and even moderate doses of radiation. Some spores on Earth have been found to be over 40 million years old and still viable. That’s more than long enough for a quick stroll across the galaxy.

Using the dinosaur-killing impact 65 million years ago was a clever way to garner attention for this analysis, but the conclusions hold true for any large Earth impact. The material thrown out of orbit is going to get around — that part is just straight-up physics. We can’t know for sure if any living organisms or biological material would survive the journey, but it’s definitely entertaining to imagine the possibilities.

Remember, Earth is just one planet out of trillions that are being constantly pelted by meteorites, too. In the words of Hara’s research paper, “the probability is almost one [100%] that our solar system is visited by the microorganisms that originated in extra solar system.”

Read more at MIT Technology Review