Kardashev Scale
From Future
The Kardashev scale is a general method of classifying how technologically advanced a civilization is, first proposed in 1964 by the Russian astronomer Nikolai Kardashev. It has three categories, based on the amount of usable energy a civilization has at its disposal and increasing logarithmically:
- Type I — A civilization that is able to harness all of the power available on a single planet, approximately 1016 W. The actual figure is quite variable; Earth specifically has an available power of 1.74×1017 W. Kardashev's original definition was 4×1012 W. (Kardashev had originally defined Type I as a "Technological level close to the level presently attained on earth", "presently" meaning 1964.)
- Type II — A civilization that is able to harness all of the power available from a single star, approximately 1026 W. Again, this figure is variable; the Sun outputs approximately 3.86×1026 W. Kardashev's original definition was 4×1026 W.
- Type III — A civilization that is able to harness all of the power available from a single galaxy, approximately 1036 W. This figure is extremely variable, since galaxies vary widely in size. Kardashev's original definition was 4×1037 W.
All such civilizations are purely hypothetical at this point. However, the Kardashev scale is of use to SETI researchers, science fiction authors, and futurists as a theoretical framework.
There is also a hypothetical "type IV", which includes such fictional species such as the time-traveling Time Lords in the television series, "Doctor Who". The exact definition of a type IV species is uncertain.


