Text 1Astronomer Mark Holland and colleagues examined four white dwarfs - small, dense remnants of past stars - in order...
GMAT Craft and Structure : (Structure) Questions
Astronomer Mark Holland and colleagues examined four white dwarfs - small, dense remnants of past stars - in order to determine the composition of exoplanets that used to orbit those stars. Studying wavelengths of light in the white dwarf atmospheres, the team reported that traces of elements such as lithium and sodium support the presence of exoplanets with continental crusts similar to Earth's.
Text 2
Past studies of white dwarf atmospheres have concluded that certain exoplanets had continental crusts. Geologist Keith Putirka and astronomer Siyi Xu argue that those studies unduly emphasize atmospheric traces of lithium and other individual elements as signifiers of the types of rock found on Earth. The studies don't adequately account for different minerals made up of various ratios of those elements, and the possibility of rock types not found on Earth that contain those minerals.
Based on the texts, how would Putirka and Xu (Text 2) most likely characterize the conclusion presented in Text 1?
Step 1: Decode and Map the Passage
Create Passage Analysis Table
| Text from Passage | Analysis |
|---|---|
| Text 1: "Astronomer Mark Holland and colleagues examined four white dwarfs—small, dense remnants of past stars—in order to determine the composition of exoplanets that used to orbit those stars." |
|
| "Studying wavelengths of light in the white dwarf atmospheres, the team reported that traces of elements such as lithium and sodium support the presence of exoplanets with continental crusts similar to Earth's." |
|
| Text 2: "Past studies of white dwarf atmospheres have concluded that certain exoplanets had continental crusts." |
|
| "Geologist Keith Putirka and astronomer Siyi Xu argue that those studies unduly emphasize atmospheric traces of lithium and other individual elements as signifiers of the types of rock found on Earth." |
|
| "The studies don't adequately account for different minerals made up of various ratios of those elements, and the possibility of rock types not found on Earth that contain those minerals." |
|
Provide Passage Architecture & Core Elements
Main Point: While Holland's team concluded that lithium and sodium traces indicate Earth-like exoplanet crusts, Putirka and Xu argue such studies inadequately consider the complexity of mineral compositions and non-Earth rock possibilities.
Argument Flow: Text 1 presents a straightforward research finding using elemental traces to infer Earth-like exoplanet crusts. Text 2 challenges this approach, arguing that focusing on individual elements oversimplifies the analysis and fails to account for alternative mineral compositions and rock types that could produce the same elemental signatures.
Step 2: Interpret the Question Precisely
What's being asked? How would Putirka and Xu characterize Holland's conclusion from Text 1
What type of answer do we need? Their likely assessment or evaluation of the conclusion's validity
Any limiting keywords? "most likely" indicates we need the best fit based on their stated position
Step 3: Prethink the Answer
- Based on our analysis, Putirka and Xu would view Holland's conclusion critically because they believe studies like Holland's overemphasize individual elements (lithium, sodium)
- They believe studies inadequately consider alternative explanations
- They believe studies fail to account for different mineral ratios and non-Earth rock types
- So the right answer should reflect their view that Holland's conclusion has significant methodological limitations - specifically that it's based on incomplete analysis that doesn't consider enough possibilities
- This suggests the conclusion was surprising because exoplanets were thought to lack crusts
- Text 2 never indicates the conclusion was unexpected - they critique the methodology, not the surprising nature of the finding
- This implies researchers are just beginning this type of work
- Text 2 references "past studies" suggesting this research area is established, not in its infancy
- Their critique focuses on analytical approach, not timing
- Matches exactly what Putirka and Xu argue: the studies have "incomplete consideration"
- They specifically say studies "don't adequately account for different minerals" and "possibility of rock types not found on Earth"
- "Questionable" captures their critical stance toward the conclusion's reliability
- Suggests the detection of lithium and sodium itself is unusual
- Text 2 doesn't question the detection capability - they accept that these elements were found
- Their criticism targets the interpretation of what these detections mean, not the detection process