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The United States government is currently taking a serious look at the moon and Mars as potential places for future human settlement for a number of reasons. First, they could be a future source of natural resources desperately needed on Earth. Second, the moon could serve as a training ground or a kind of stepping stone for later journeys to Mars. Therefore, the moon is already on NASA’s docket for further exploration within the next couple of decades, which, at least to some experts, is completely unnecessary mainly due to the needless risks involved. With Mars looming as the eventual long-term goal, serious questions exist as to whether the dangers and difficulties of a lunar settlement are too extreme and unnecessary. The moon’s relatively harsh environment and the greater potential of natural resources on Mars are major reasons that make lunar settlements too great a liability and why the moon should be bypassed.
One major reason a lunar settlement is too hazardous is the contrast between the environments of the moon and the red planet. Numerous scientists believe the moon is too difficult for human settlement as compared to Mars. The fact that the moon has no atmosphere poses the greatest threat to human beings. Atmosphere is crucial because it protects humans and all other life from continuous bombardment of cosmic radiation caused by sources such as the sun. This radiation is especially dangerous to humans because it increases the risk of cancer and can negatively alter and mutate DNA. On the other hand, while Mars’s atmosphere is significantly thinner than Earth’s, at least it has one and would create some sort of protective barrier for humans.
Another important characteristic necessary for sustainable human settlement is water, of which the moon is believed to have none. A If lunar settlements are to be successful, water will be a key component and must be brought with the colonists and continually supplied by further expeditions from Earth, which means they will have a limited capacity of it. B Conversely, Mars contains vast quantities of water ice, dry ice, and also snow. C There is also ample evidence that water once existed at the surface of Mars and might return in the future if the planet warms. D With increased technological advances in conversion capabilities, the potential for settlers to remain on Mars indefinitely by being increasingly self-sufficient makes Mars a much more attractive goal as a space colony than the moon.
Future colonists will not only benefit from potential water sources on Mars; the planet is also rich in other basic elements vital to sustained life. These resources include nitrogen, oxygen, and hydrogen. Mars also contains many minerals that contain iron, silicon, and magnesium, which can be used in productive ways. For example, silicon can be used to make solar cells to store energy and create electricity. Hydrogen can be extracted from water sources and used as fuel. Moreover, it can be combined with nitrogen to form fertilizing materials necessary to a sustainable colony. Due to these factors, Mars would be a more successful candidate for exploration and settlement because it contains the basic resources necessary for humans to survive more independently of aid from Earth than they would on the moon.
Clearly, any future settlements on Mars or the moon will be monumental efforts for the space agencies and astronauts involved. The expenses incurred will be extreme and are a further reason why plans and implementation should focus on the project, which has the greater potential of long-term success. While the moon may serve as a temporary training ground for Mars, it could end up becoming a major diversion from Mars and place humans in too great a risk with too little benefit. Because the environment of Mars is more similar to that of Earth and it contains important resources necessary to sustain life, it should be the one and only option for any kind of long-term human settlement. Furthermore, the moon has been eclipsed by mankind, and it is only natural that Mars be the next step for space exploration. Finally, the habitation of Mars would not only be a milestone in space but also an excellent opportunity for mankind to redeem itself from past exploits on Earth and preserve and make the best use of the natural resources Mars has to offer.
docket: a list of things to be done; an agenda
11. According to paragraph 1, which of the following is true of space settlements?
A They should have already been instigated by NASA many years ago.
B They must first incorporate the moon as a practice arena for Mars exploration.
C They could prove to be a last resort for gaining life-sustaining supplies.
D Their danger cannot be justified due to the risk to human life and high cost.
12. The word looming in the passage is closest in meaning to
A expanding
B competing
C waiting
D emerging
13. The author discusses environments in paragraph 2 in order to
A justify why the moon is a more practical place than Mars for human settlement
B express the notion that Mars poses less life-threatening hazards than the moon
C propose that cosmic radiation would have little effect on the lunar colonists
D indicate that lunar settlements are futile because the moon has no atmosphere
14. According to paragraph 2, the atmosphere on Mars would
A change the genetic makeup of humans and cause their DNA to change and mutate
B protect humans completely from harmful cosmic radiation coming from space
C cause humans to be more openly exposed to potentially fatal illnesses
D give human colonists a safety shield against dangerous cosmic effects
15. Look at the four squares [■] that indicate where the following sentence could be added to the passage.
If supplies are delayed for one reason or another, the entire project and the livelihood of the colonists could be in serious jeopardy.
Where would the sentence best fit?
Click on a square [■] to add the sentence to the passage.
16. Which of the sentences below best expresses the essential information in the highlighted sentence in the passage? Incorrect answer choices change the meaning in important ways or leave out essential information.
A The moon is easier to adapt to because of advances in technology and self-sufficiency.
B Having settlers staying on Mars is more appealing because of its potential as a colony.
C Mars may be a better long-term option than the moon because of the most recent technology.
D Conversion capabilities will enable settlers to make traveling to the moon a more viable goal.
17. What can be inferred about water sources on Mars?
A They exist in liquid form below the surface and ice at the immediate surface.
B They are not present at the moment though they probably once were.
C They will be easily converted into liquid forms necessary for life.
D They are not known to be present in a fluid state above or below the surface.
18. According to paragraph 4, what is true about the mineral content of Mars?
A The planet lacks the fundamental elements of carbon and nitrogen.
B Most are in their rawest forms and cannot be utilized completely.
C Some will help future colonists create their own sources of energy.
D Their levels do not reach the magnitude of those found on the moon.
19. The author of the passage implies that future space exploration
A will look past Mars and include other planets within its parameters
B needs to move ahead to new frontiers instead of going back to old ones
C is in its infancy and will require a fresh vision from scientists for it to succeed
D does not make sense if humans only wish to search for alien life forms
20. Directions: An introductory sentence for a brief summary of the passage is provided below. Complete the summary by selecting the THREE answer choices that express the most important ideas in the passage. Some answer choices do not belong in the summary because they express ideas that are not presented in the passage or are minor ideas in the passage. This question is worth 2 points .
Settlements on Mars would be challenging like the moon, yet they would be able to sustain life much better than Earth’s satellite.
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A The moon would provide an excellent training ground for future expeditions to Mars.
B The environment of Mars would be more receptive to humans than that of the moon.
C Rich in nitrogen and hydrogen, the moon can sustain life more easily than Mars.
D Potential sources of water on Mars make it a better long-term opt ion.
E Long-term exposure to radiation on an atmosphere-less Mars could prove fatal.
F Minerals found on Mars can help colonists create independent energy sources.
Drag your answer choices to the spaces where they belong.
To remove an answer choice, click on it. To review the passage, click on View Text .