|
The Kardashev scale is a method of measuring a civilization's level of technological advancement, based on the amount of energy a civilization is able to utilize.〔 The scale has three designated categories called ''Type I'', ''II'', and ''III''. A Type I civilization uses only resources available on its home planet, Type II harnesses all needed energy from its local star, and Type III of its galaxy.〔 The scale is only hypothetical, but it puts energy consumption in a cosmic perspective. It was first proposed in 1964 by the Soviet astronomer Nikolai Kardashev. Various extensions of the scale have been proposed since, from a wider range of power levels (types 0, IV and V) to the use of metrics other than pure power. ==Definition== In 1964, Kardashev defined three levels of civilizations, based on the order of magnitude of power available to them: Type I : "Technological level close to the level presently attained on earth, with energy consumption at ≈4 erg/sec (4 × 1012 watts)." Guillermo A. Lemarchand stated this as "A level near contemporary terrestrial civilization with an energy capability equivalent to the solar insolation on Earth, between 1016 and 1017 watts."〔.〕 Type II : "A civilization capable of harnessing the energy radiated by its own star (for example, the stage of successful construction of a Dyson sphere), "with energy consumption at ≈4 erg/sec."〔 Lemarchand stated this as "A civilization capable of utilizing and channeling the entire radiation output of its star. The energy utilization would then be comparable to the luminosity of our Sun, about 4 erg/sec (4×1026 watts)."〔 Type III : "A civilization in possession of energy on the scale of its own galaxy, with energy consumption at ≈4 erg/sec."〔 Lemarchand stated this as "A civilization with access to the power comparable to the luminosity of the entire Milky Way galaxy, about 4 erg/sec (4×1037 watts)."〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Kardashev scale」の詳細全文を読む スポンサード リンク
|