1 . “Pale moon rains. Red moon blows. White moon neither rains nor snows.” For generations, people have watched the moon for signs of changes in the weather. The moon does, in fact, affect the Earth’s climate and weather patterns in several unnoticeable ways.
The most obvious effect the moon has on the Earth can be seen in the ocean tides (潮汐). A world without tides would have very different weather systems. Tides are one factor that influences the movement of ocean currents, which move warm or cool water about the Earth. Warm ocean currents bring warmer wetter weather, while cold ocean currents bring colder drier weather.
While the lunar nodal cycle is set to bring marked change over the coming decades, the moon affects the Earth in a few other little-known ways on a shorter timescale.
The moon is also thought to affect polar temperatures and contribute to fluctuations (波动) in the extent of Arctic ice. Satellite measurements have shown that the poles are 0.55℃ warmer during a full moon. In addition, tidal forces act to break up ice sheets and change ocean heat flows, converting the amount of ice in the Arctic Ocean.
The moon’s influence, sometimes unnoticeable and sometimes strong, has had a formative impact on life on Earth. Some scientists argue that it is the moon that made life possible in the first place. The moon steadies the Earth as it spins on its axis (轴), helping to give us a stable climate. Without it, the Earth would rock more irregularly. The poles would move obviously in relation to the Earth’s orbit. Seasons, days and nights would all look very different. The moon is closest to the Earth in the universe, without which the Earth would be a very lonely place.
1. What is the author’s purpose of writing paragraph 1?| A．To draw people’s attention to the text. | B．To teach people signs of weather changes. |
| C．To show people how to appreciate the moon. | D．To tell people to prepare for extreme weather. |
| A．The world weather system. | B．The impact of ocean tides. |
| C．The movement of ocean tides. | D．The reasons for warmer weather. |
| A．Changing. | B．Speeding. | C．Determining. | D．Keeping. |
| A．Health. | B．Entertainment. | C．Science. | D．Sports. |
2 . One of the biggest barriers to a manned mission to Mars is the fuel problem. If future Mars explorers ever want to return to Earth, they’ll not only need enough fuel to get to Mars, but also enough to get back home. And fuel is heavy. If the plan is to pack it from Earth for the whole journey, then that adds a lot of weight to the aircraft. It’s a difficult problem.
Now, in a new plan outlined in an article by a NASA team leader Kurt Leucht, the dream of making fuel right on Mars itself appears to be a real possibility. And the only raw material needed to make the rocket fuel? Martian soil.
The NASA team calls the method “in situ resource utilization”, or ISRU. It involves extracting（提炼）water from Mars’ distinctive red-colored dirt and using a process called electrolysis（电解）to separate water into hydrogen and oxygen. The hydrogen can then be combined with carbon, which is plentiful in Mars’ atmosphere, to make methane, which can be used as rocket fuel.
Of course, all of this requires time and an on-site factory that’s up to the task. For that, NASA is developing a team of robots that can be set up on Mars years in advance of a return trip to Earth, which will tirelessly work to manufacture the rocket fuel.
The whole plan does have one small challenge. Namely, it depends on the water content of Martian soil. If we start digging and there’s no water, or far less of it than expected, that could be a problem. But scientists are becoming increasingly confident that Mars’ soil actually has a fair amount of water locked into it, which is also enough for the survival needs of astronauts who plan to stay a while on the Red Planet.
“This technology will one day allow humans to live and work on Mars,” wrote Leucht, “and return to Earth to tell the story.”
1. What is one of the problems faced by Mars explorers?| A．They cannot carry enough fuel to return to Earth. |
| B．They have great difficulty surviving on Mars. |
| C．They need a large aircraft to carry enough fuel. |
| D．They cannot carry enough food to feed themselves. |
| A．By releasing a lot of carbon. | B．By providing water resources. |
| C．By producing methane directly. | D．By absorbing hydrogen in the air. |
| A．By doing experiments on Earth first. | B．By training factory workers on Mars. |
| C．By preparing a return trip in advance. | D．By employing robots as workers on Mars. |
| A．Doubtful. | B．Optimistic. | C．Concerned. | D．Unclear. |
