题目内容

Frank Sietzen, a journalist and coauthor of "New Moon Rising", a chronicle of the development of the new NASA vision, has spent the better part of the past six months leafing through these contracts in order to divine the agency's plans. He says that because the CEV must be compatible with other components of the vision, the contracts give de tails of how NASA is planning to explore the moon and Mars.
According to Mr. Sietzen, the new moonships will have three components that will be launched separately and then bolted together in orbit—unlike NASA's previous moon rocket, the Saturn 5, in which everything went up at once. One component will be the CEV. The second will be an Earth-departure stage—a rocket that provides the oomph needed to push the ship on its way to the moon. The third will be the "lunar surface access module", or lunar lander, to the man in the street.
The decision to assemble the new moonships in orbit lowers the cost of developing the rocket needed to get them off the Earth's surface. Mr. Sietzeen predicts that in about a month's time, when NASA picks two bidders for a CEV, it will announce what this rock et will be—and that it will be based on the technology now used to launch the shuttles.
It is also, he adds, possible to work out from the contracts what the masses of the different components will be. These suggest that four astronauts will travel to the moon and six astronauts to Mars, and that the access module will sometimes fly as an unmanned truck carrying cargo to the moon's surface.
He predicts that there will be three phases of lunar exploration. Initial landings of two to three days will pick up where Apollo left off. Subsequent trips to rougher terrain will last for a week to ten days. And eventually a base camp will be established at one of the poles. This will be occupied for periods ranging from 90 days to a year, and will lead to a permanent manned presence that would act as a prototype Mars base.
The best title for this text could be

A. CEV and NASA's lunar plan.
B. Frank Sietzen's legendary affection.
CEV and its earth orbit.
D. Frank Sietzen's astronomical feats.

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