One feature of the solar system that does not require complicated explanation is the presence of craters on the surfaces of some of the planets and moons. These surfaces are hammered by impacts, and for some objects these impacts define their characteristics. Craters tell the story of the solar system’s history.

On Earth, at least one large-scale impact led to extinction. But when it comes to life, these influences can give or take away. Although the Chicxulub impact wiped out the dinosaurs, other impacts could spread life from planet to planet.

The idea that life spreads from world to world dates back to ancient Greece and the philosopher Anaxagoras. it is called panspermiaand while it’s not necessarily mainstream scientific thinking, it has survived. This idea has received some support from a growing understanding that the chemical building blocks of life are more widespread than we thought.

Now, new research on extremophiles shows that at least some of them can survive being ejected from Mars by an asteroid impact. Not only can they withstand the extremely high pressures of direct impact, but they can also survive interplanetary travel, despite its many dangers. This can occur if it becomes embedded in debris due to impact.

The research is “Extremophiles survive the temporary pressures associated with impact ejection from Mars.” and published on PNAS Nexus. The first author is Lily Zhao, a graduate student in the Department of Mechanical Engineering at Johns Hopkins University.

“Massive impacts are ubiquitous in the solar system, and the likelihood of life survival after impact events plays an important role in planetary protection, the search for extraterrestrial life, and the evaluation of the panspermia hypothesis,” the authors write. “Shocks create very high stresses over short periods of time, resulting in extreme pressures and high loads. Can microorganisms withstand such extreme conditions?” the researchers ask.

To find out, they chose an extremophile named . Deinococcus radioduransIt is known to be able to withstand dangerous conditions in space. D. radiodurans has been the subject of many studies of extremophiles. It is the most radiation-resistant life form we know of, and can withstand cold, dehydration, vacuum, and even acid. Because of their resistance to these hazards, they are sometimes referred to as polyextremophiles.

In a laboratory experiment, the researchers simulated a shock by applying extreme pressure to D. radiodurans for a short period of time. They then measured how many of the biological samples survived, how the survivors repaired the damage, and how they responded to the impact at a molecular level.

“We kept trying to kill it, but it was really hard to kill.” – Lily Chao, Johns Hopkins University

*This diagram shows how a laboratory experiment was performed. This is called a pressure shear plate impact experiment, in which a projectile with a wedge and a flyer plate impacts two steel plates sandwiching a D. radiodurans sample. This setup keeps pressure and shear forces equal throughout the sample. Laser interferometry and lateral displacement interferometry measure and calculate stress on organisms as they change over time. Image credit: Zhao et al. 2026.PNASNexus*

RNA from the surviving samples was extracted and studied. It was found that as the pressure increases, the stress placed on the organism also increases. However, survival rates were high in some experiments.

“We demonstrated that D. radiodurans, an extremophile, has significantly high viability and viability even after exposure to pressures of up to 3 GPa,” the authors write. “As pressure increased, D. radiodurans showed indicators of increased biological stress, as determined by transcriptional analysis of affected samples.”

*This graph shows how D. radiodurans responded to impact pressure. One gigapascal (GPa) is about 10,000 times the normal Earth’s surface pressure, so some of the extreme environment samples withstood extreme pressures. The survival rate was approximately 95% at 1.4 GPa, 94% at 1.6 GPa, 86% at 1.9 GPa, and 60% at 2.4 GPa. Image credit: Zhao et al. 2026.PNASNexus*

“Our results suggest that microorganisms can survive in much harsher conditions than previously thought, and may even be able to survive in conditions that lead to the formation of ejecta that can travel across planetary systems,” the researchers wrote.

“Life could actually survive being ejected from one planet and moving to another,” said senior author KT Ramesh, an engineer who studies the behavior of materials in extreme conditions. “This is a really big event that changes the way we think about how life began and how life began on Earth.”

The researchers also studied the post-impact samples to observe cell damage. They used transmission electron microscopy (TEM) to compare unshocked control samples to samples exposed to 1.4 GPa and 2.4 GPa. They found “structural and morphological changes resulting from these transient pressures at higher pressures.”

*According to the authors, cells exposed to 1.4 GPa retain morphology and membrane/cell wall structure similar to controls. However, cells exposed to 2.4 GPa show internal damage and cell wall damage. Image credit: Zhao et al. 2026.PNASNexus*

However, the main result is that D. radiodurans appears to be able to withstand very high pressures, albeit temporarily, with minimal effects.

“We demonstrated that D. radiodurans, an extremophile, has significantly higher survival rates and viability even after exposure to pressures of up to 3 GPa. As pressure increased, D. radiodurans exhibited indicators of increased biological stress, as determined by transcriptional analysis of affected samples.”

“We expected that the first pressure would kill them,” lead author Zhao said in the paper. press release. “We started shooting more and more. We kept trying to kill it, but it was really hard to kill.”

In fact, the experimental setup succumbed to pressure before all D. radiodurans.

Impacts on Mars could push samples up to 5 GPa, and even higher depending on various factors. Still, the fact that D. radiodurans survived up to 3 GPa is good news for panspermia enthusiasts.

“We have shown that it is possible for life to survive large-scale impacts and eruptions,” Zhao said. “That means life could travel between planets. Maybe we’re Martians!”

However, this result applies to more than just panspermia. D. radiodurans’ ability to withstand extreme pressures means there is a path through which it can survive inadvertent travel from Earth to Mars or other locations in rovers or landers.

“We may need to be very careful about which planets we visit,” Ramesh says.

“These discoveries have important implications for our understanding of the limits of life, planetary protection, space mission design, and the potential for dispersal of life throughout the solar system,” the authors conclude.