Planets orbiting white dwarfs may have conditions suitable for life. While these stellar remnants no longer generate their energy, their rapidly shrinking habitable zones could still provide enough time and resources for biological processes to emerge. This challenges previous assumptions that planets in these systems would be inhospitable due to their dynamic temperature fluctuations. The research introduces a model that examines whether two critical processes which are photosynthesis and ultraviolet (UV)-driven abiogenesis could take place in these zones, suggesting that life could persist around these stars for billions of years.

White Dwarf Habitability Assessed

According to a study published in The Astrophysical Journal Letters, a team that was led by Caldon Whyte from the Florida Institute of Technology explored how long an Earth-like planet could sustain life-supporting conditions in the narrowing habitable zone of a white dwarf. White dwarfs, formed when stars like the Sun exhaust their nuclear fuel and collapse into dense remnants, undergo a gradual cooling process. This results in their habitable zones shifting inward, limiting the time a planet could remain within the range where liquid water can exist.

By simulating a planet orbiting a white dwarf over a span of seven billion years, the study assessed the energy available for photosynthesis and UV-driven abiogenesis. The results indicated that despite the constricting habitable zone, sufficient energy was received for both processes to function. This suggests that white dwarf systems, previously overlooked in the search for extraterrestrial life

Potential for Alien Life in Unlikely Systems

In an official press release of the Florida Institute of Technology, Whyte noted that while main-sequence stars like the Sun provide ample energy for photosynthesis and UV radiation, smaller stars such as red dwarfs and brown dwarfs do not offer the same conditions. Scientists may now reconsider these stellar remnants in their ongoing search for life beyond Earth