The union will start with a European-led orbiter in 2016, and continue with surface rovers in 2018, and then perhaps a network of landers in 2018.

这个联合项目将在2016年以一个欧洲主导的轨道飞行器项目开始，2018年开始火星车项目，之后是2018年的着陆工程。

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Will we be doing orbiters or landers?

BBC: ��Six minutes of terror��

If all landers make it to the surface of Mars, they will represent three more flags on a largely unexplored map.

BBC: Gusev crater (Nasa)

The twin landers, each the size of a desk and weighing 375 pounds (170 kilograms), will ramble dozens of meters a day, drilling into rocks and scooping up soil in preliminary field studies to help identify ancient oases.

CNN: Race to Mars begins a distant search for life