Details

Autor(en) / Beteiligte

• Mancinelli, R.L.

Titel

Prospects for the evolution of life on Mars: Viking 20 years later

Ist Teil von

• Advances in space research, 1998, Vol.22 (3), p.471-477

Ort / Verlag

Elsevier Ltd

Erscheinungsjahr

1998

Quelle

Elsevier Journal Backfiles on ScienceDirect (DFG Nationallizenzen)

Beschreibungen/Notizen

• During the summer of 1976 the two Viking spacecraft arrived at Mars. Their primary objective was to determine if there was life on Mars. The results of the three life detection experiments aboard the two landers, while not definitive, did not show the presence of extant life. In addition, the GC-MS analyses did not find any organic matter in the Martian regolith at either landing site. Although Viking found no life, it provided data to help explain why no extant life was found at the Martian surface: The surface of Mars is an oxidizing, desiccated environment devoid of liquid water. However, data from the chemical analyses of the regolith conducted during the Viking mission as well as recent analyses of SNC meteorites suggests that all of the chemical elements necessary for life to arise occur on Mars. Further, Mars and Earth accreted from the same interplanetary material suggesting that the early chemical and physical environments of the two planets may have been similar. If this is true then the prospects for the evolution of life on Mars rests on the degree and the duration of similarity between Earth and Mars. Data gathered to date suggests that if liquid water existed on the surface of Mars for sufficient time the probability for life to have arisen is quite reasonable.