Space & Astronomy

Martian organisms might have hitched a ride to primordial Earth

By T.K. Randall
March 7, 2026 ·  11 comments

Image Credit: (PD) NASA via Wikimedia Commons Panspermia is the name given to the hypothesis that life did not necessarily originate on Earth and that organisms can hitch a ride on asteroids, comets and other objects to travel from one planet to another, essentially seeding new worlds across the cosmos.

It has long been theorized that this may have been how life first arrived on Earth and that primitive organisms might have even originated on Mars before finding their way here.

Now, according to a new study, a particularly resilient bacterium known as Deinococcus radiodurans may be one such organism given its remarkable ability to withstand the forces of ejection from a planet's surface following an asteroid impact.

This, coupled with its innate ability to survive in extremely cold and dry environments, could make it an analog of a life form capable of traveling on an asteroid from one world to another.To simulate the conditions of an impact, the researchers fired projectiles through a gas-powered gun and found that the bacteria not only seemed to be highly resistant to damage, but that the genes responsible for DNA repair and cell maintenance became more active the greater the force exerted.

While the results do not prove that life travels between planets, they do suggest that microbes could potentially survive the violent ejection stage of such a journey.

"Life might actually survive being ejected from one planet and moving to another," said study co-author Kaliat Ramesh of Johns Hopkins University in Maryland.

"This is a really big deal that changes the way you think about the question of how life begins and how life began on Earth."

Source: Space.com | Comments (11)

Tags: Mars, Earth