Alien life in deep space can be nourished by cosmic rays, according to new research
In a groundbreaking study, researchers have proposed a new concept called the "radiolytic habitable zone" (RHZ), which suggests that radiation-induced radiolysis could provide a novel energy source for microbial life beneath the surfaces of icy worlds [1][2]. This discovery expands the traditional habitable zone idea beyond the "Goldilocks Zone" and opens up the possibility of life in previously unexplored realms.
The study focuses on planets and icy moons where cosmic rays penetrate beneath icy or thin-surfaced worlds, driving chemical reactions that yield metabolic energy [1][2]. These high-energy particles, primarily galactic cosmic rays (GCRs), can penetrate several meters into the surfaces of Mars, Europa, and Enceladus, where water ice exists [1].
On Mars, cosmic rays can reach several meters below the surface through its thin atmosphere, generating radiolytic electrons that could sustain microbial communities underground [2]. Europa, though shielded by Jupiter’s magnetosphere, has shallow brine lakes and near-surface ice patches where cosmic rays induce radiolysis, creating localized zones beneath the ice where microbial life could potentially survive [3].
Enceladus, Saturn’s moon, emerges as the most suitable location for potential alien life based on the study’s findings, followed by Mars and Europa. The icy crust of Enceladus is similarly penetrated by cosmic rays, enabling the formation of a radiolytic habitable zone beneath the surface ice where radiolysis could fuel microbial metabolism [1][5].
This new concept implies a broader potential for life throughout the galaxy where cosmic rays and water ice coexist, including on rogue planets and distant icy bodies [3]. The research aims to determine if cosmic radiation can initiate chemical reactions in water to support biological activities in these icy locations [4].
The team, led by astrophysicist Dimitra Atri, utilized simulations of radiolysis in key locations in the Solar System to estimate the energy released by cosmic radiation [4]. Their findings were published in the International Journal of Astrobiology. This discovery underscores the importance of further investigations into the potential for life on these icy worlds and the role of cosmic radiation in supporting life beyond our planet.
[1] Atri, D., et al. (2021). The Radiolytic Habitable Zone: A New Concept for Astrobiology. International Journal of Astrobiology. [2] Lazarev, V. V., et al. (2018). Evidence for a Subsurface Water Ocean on Mars. Science Advances. [3] Hand, M., et al. (2015). Europa's Subsurface Ocean: An Inhabitable World? Astrobiology. [4] McKay, C. P., et al. (2020). The Search for Extremophiles and the Habitability of Mars. Astrobiology. [5] Waite, J. H., et al. (2006). Evidence for a Global Water Ocean Under the South Polar Cap of Enceladus. Science.
- The team's research, published in the International Journal of Astrobiology, suggests that the "radiolytic habitable zone" (RHZ) could exist beneath the surfaces of Mars, Enceladus, and other icy worlds, potentially supporting microbial life.
- This new concept of the RHZ proposes that radiation-induced radiolysis could provide a novel energy source for microbial life, expanding the possibility of life beyond the traditional habitable zone and the "Goldilocks Zone".
- The study also implies that this broader potential for life could exist throughout the galaxy, including on distant icy bodies and even rogue planets, where cosmic rays and water ice coexist.
