托福阅读训练:火星探索(2)

如果有个人对时尚很不敏感,我们就说他是“火星来的”,我们也会经常调侃自己:我要回火星去了;我是火星人。这说明,我们对火星都很感兴趣,确实,近年来,各国对火星的探索一直都没有停过。

  ESA hopes to land humans on Mars between 2030 and 2035.This will be preceded by successively larger probes, starting with the launch of the ExoMars probe and a joint NASA-ESA Mars sample return mission.

  Mars Direct, an extremely low-cost human mission proposed by Bob Zubrin, a founder of the Mars Society, uses heavy-lift Saturn V class rockets, such as the Space X Falcon 9, or, the Ares V, to skip orbital construction, LEO rendezvous, and lunar fuel depots. A modified proposal, called "Mars to Stay", involves not returning the first immigrant/explorers immediately, if ever. Dean Unick has suggested the cost of sending a four to six person team is one fifth to one tenth the cost of returning that same four to six person team; twenty settlers could be sent for the cost of returning four.