The Viking lander missions showed the present surface environment of Mars to be unfavourable for life due to the absence of liquid water, intense UV radiation, and oxidizing soils.

维京登陆任务显示，由于没有水，强紫外辐射，氧化性的土壤，当前火星表面不适合生命生存。

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Each mission had a satellite designed to photograph the surface of Mars from orbit, and to act as a communication relay for the Viking lander that each mission carried.

每次任务都发射一枚具备从火星轨道拍摄火星表面能力的人造卫星，同时充当与海盗登陆者进行联络的中间站。

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In addition, the team has located all three of the other successful Mars landers, including Viking Lander 2 whose discovery was also announced on May 5th.

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There have been three successful Mars lander missions, the Viking 1 and Viking 2 in 1976, and the Pathfinder in 1997.

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When we come back we're going to switch gears again and talk about the 30th anniversary of the Martian lander, the Viking, landing on Mars 30 years ago this week.

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