A new study led by researchers from the Blue Marble Space Institute of Science explores the idea that advanced extraterrestrial civilizations might eventually reach a level where they harvest stellar mass directly, potentially evolving into “stellivores”—civilizations that consume stars as a primary energy source. This concept expands on the well-known Kardashev Scale, a framework introduced in 1964 to categorize civilizations based on their energy consumption capabilities, from utilizing planetary resources (Type I), to harnessing all the energy from their star (Type II), to controlling energy at the galactic level (Type III). Traditionally, this scale has served as a guide for searching for technosignatures, including megastructures around stars, like Dyson Spheres.

The research, conducted by Jacob Haqq-Misra and colleagues, reinterprets the Kardashev Scale as representing the theoretical limits of a civilization’s energy use but not necessarily a pathway that every advanced civilization would follow. According to the team, some civilizations may achieve an equilibrium by balancing exploration with exploitation, without ever reaching the full energy potential suggested by the Kardashev Scale. Others may develop energy-harvesting techniques that bypass traditional energy limits, focusing instead on consuming stellar material directly.

Haqq-Misra suggests that stellivorous civilizations could hypothetically exceed the energy limits of the Kardashev Scale, moving beyond merely collecting stellar light to consuming star mass itself. This shift could offer a pathway for limitless energy, assuming that such advanced civilizations could overcome the challenges of transforming stellar matter into usable energy according to Einstein’s mass-energy equivalence (E=mc²).

This idea also proposes new directions for the Search for Extraterrestrial Intelligence (SETI). Future SETI surveys could monitor “accreting binaries,” which are binary star systems where one star draws mass from another, to detect signs of unusual behavior that might hint at technological activity. If some of these systems indeed involve stellivorous civilizations, it could provide unprecedented insights into extraterrestrial energy use and technology.

Ultimately, this study challenges us to expand our perspectives on what advanced civilizations might look like and consider the possibility of civilizations vastly different from humanity in their approach to energy consumption and expansion.