Star: average rate of star formation in our galaxy.Star with two planets: fraction of those stars that have planets.Three planets: average number of planets that can potentially support life per star that has planets.Cell: fraction of planets that could support life that develop life at some point.Gear: fraction of planets with life that develop intelligent life.Radio signal: fraction of civilizations that develop a technology that send detectable signs of their existence into space.Clock: length of time civilizations broadcast detectable signals into space.<br/>德雷克方程<br/>Collection、remix+17890、remix+169903、remix+230920、remix+242496、Set of icons that pictorially represent factors of the Drake Equation.<br/>採集、混音+ 17890、混音+ 169903、混音+ 230920、混音+ 242496、圖標表示德雷克方程的因素的圖標集。<br/>資料來源:openclipart ( https://openclipart.org/ )
修改日期:2026-05-29