venus-earth-mars comparative climatology and the search for life in the solar systemvenus-earth-mars比较气候学和太阳系中寻找生命.pdfVIP

Life 2012, 2, 255-273; doi:10.3390/life2030255 OPEN ACCESS life ISSN 2075-1729 /journal/life Article Venus-Earth-Mars: Comparative Climatology and the Search for Life in the Solar System Roger D. Launius Division of Space History, National Air and Space Museum; Smithsonian Institution, P.O. Box 37012, NASM Room 3550, MRC 311, Washington, DC 20013-7012, USA; E-Mail: launiusr@; Tel.: 202-633-2428 Received: 8 August 2012; in revised form: 31 August 2012 / Accepted: 7 September 2012 / Published: 19 September 2012 Abstract: Both Venus and Mars have captured the human imagination during the twentieth century as possible abodes of life. Venus had long enchanted humansall the more so after astronomers realized it was shrouded in a mysterious cloak of clouds permanently hiding the surface from view. It was also the closest planet to Earth, with nearly the same size and surface gravity. These attributes brought myriad speculations about the nature of Venus, its climate, and the possibility of life existing there in some form. Mars also harbored interest as a place where life had or might still exist. Seasonal changes on Mars were interpreted as due to the possible spread and retreat of ice caps and lichen-like vegetation. A core element of this belief rested with the climatology of these two planets, as observed by astronomers, but these ideas were significantly altered, if not dashed dur