Question 122·Medium·Central Ideas and Details
In the last decade, low-cost CubeSat spacecraft have quietly delivered striking images of solar storms, tracked methane plumes from orbit, and even tested new propulsion systems in deep space. Yet these achievements rarely make headlines. News coverage and public discussion still center on multibillion-dollar flagships like the James Webb Space Telescope, leading many to assume that cutting-edge discoveries can come only from massive hardware. As a result, the role CubeSats play in advancing space science often goes unrecognized, despite their growing record of innovation and success.
Which choice best expresses the main idea of the text?
For main idea questions, read the whole passage, but pay special attention to the first sentence (often introduces the topic) and the last sentence (often states the takeaway). Then, in your own words, sum up what the author is mainly saying, including any contrast or cause-and-effect they highlight. Next, eliminate answer choices that (1) add new details not mentioned, (2) focus on minor details instead of the whole paragraph, or (3) contradict the passage’s tone or message. Finally, pick the choice that best matches your own short summary of the passage.
Hints
Look at the beginning and end
Reread the first sentence and the last sentence. What do they say about what CubeSats do and how people think about them?
Notice contrast words
Focus on words like “Yet” and phrases like “As a result”. What problem or contrast is the author pointing out about CubeSats versus big flagship missions?
Beware of new ideas
Check whether each answer choice matches information directly stated in the passage. Eliminate any choice that talks about cost trends, accuracy problems, or how most missions work if the passage never says that.
Think big picture, not details
Ask yourself: overall, is the author mainly describing technical problems, rising costs, mission dominance, or how recognition and attention are distributed?
Step-by-step Explanation
Clarify the task: main idea
The question asks for the main idea of the text, not a small detail. You should look for a choice that sums up the whole paragraph, especially the relationship between CubeSats and larger, expensive missions.
Identify the key points in the passage
Read the passage and note what is emphasized:
- First sentences: CubeSats are low-cost spacecraft that have done impressive things (images of solar storms, tracking methane, testing propulsion in deep space).
- Middle: “Yet these achievements rarely make headlines.” News and public talk focus on multibillion-dollar flagships like the James Webb Space Telescope.
- End: Because attention goes to those big missions, people often do not recognize the role CubeSats play, even though they have a strong record of innovation and success.
So the paragraph has two main ideas working together: CubeSats do valuable scientific work, and that work is mostly overlooked because attention goes to big, expensive missions.
Check each answer against the passage
Now compare each option to what the passage actually says:
- One option should mention both CubeSats’ real achievements and the fact that public attention focuses elsewhere, causing those achievements to be overlooked.
- Eliminate any options that introduce new ideas not in the passage (like cost problems, accuracy problems, or claiming CubeSats dominate deep-space missions).
Match the best summary to the passage
Only one choice captures both parts of the main idea: that CubeSats have made important scientific contributions and that these contributions are often ignored because attention and headlines go to high-profile, expensive missions. That is exactly what choice D) "CubeSats' scientific contributions are frequently overlooked because high-profile, expensive missions attract most of the attention." says, so D is the correct answer.