ResearchersStudy yearEstimated average velocityMurai and Fujimoto1980344 km/sKallivayalil and colleagues2006378 km/sGardiner and colleagues1994297 km/...
GMAT Information and Ideas : (Ideas) Questions
| Researchers | Study year | Estimated average velocity |
|---|---|---|
| Murai and Fujimoto | 1980 | 344 km/s |
| Kallivayalil and colleagues | 2006 | 378 km/s |
| Gardiner and colleagues | 1994 | 297 km/s |
In 2006, Nitya Kallivayalil and colleagues calculated the most accurate estimate yet of the average velocity (in kilometers per second) of the Large Magellanic Cloud (LMC) galaxy. Before the 2006 study, estimates of the average velocity were low enough for the LMC to maintain an orbit around the Milky Way galaxy, but according to an analysis by Gurtina Besla and colleagues, the estimated velocity from the 2006 study is too high for the LMC to maintain such an orbit. Therefore, if Besla and colleagues are correct, the maximum average velocity for the LMC that would allow it to maintain orbit around the Milky Way is likely ______
Which choice most effectively uses data from the table to complete the statement?
above 344 km/s but below 378 km/s.
above 297 km/s but below 344 km/s.
above 378 km/s.
below 297 km/s.
Step 1: Decode and Map the Passage
Part A: Create Passage Analysis Table
| Text from Passage | Analysis |
|---|---|
| "In 2006, Nitya Kallivayalil and colleagues calculated the most accurate estimate yet of the average velocity (in kilometers per second) of the Large Magellanic Cloud (LMC) galaxy." |
|
| "Before the 2006 study, estimates of the average velocity were low enough for the LMC to maintain an orbit around the Milky Way galaxy" |
|
| "but according to an analysis by Gurtina Besla and colleagues, the estimated velocity from the 2006 study is too high for the LMC to maintain such an orbit." |
|
| "Therefore, if Besla and colleagues are correct, the maximum average velocity for the LMC that would allow it to maintain orbit around the Milky Way is likely ______" |
|
Part B: Provide Passage Architecture & Core Elements
Visual Structure Map:
[2006 STUDY] - Most accurate estimate (378 km/s from table)
[PRE-2006 CONTEXT] - Earlier estimates allowed orbit (344 km/s, 297 km/s from table)
[BESLA ANALYSIS] - 2006 estimate too high for orbit
[LOGICAL QUESTION] - What is the maximum that would allow orbit?
Main Point: We need to determine the maximum velocity that would allow the LMC to orbit the Milky Way, given that pre-2006 estimates were acceptable but the 2006 estimate is too high.
Argument Flow: The passage establishes that the 2006 study provided the most accurate velocity estimate, then contrasts this with earlier estimates that were considered low enough for orbital maintenance. However, Besla's analysis suggests the 2006 estimate is too high for orbit, leading us to determine where the maximum orbital velocity threshold lies.
Step 2: Interpret the Question Precisely
This is a fill-in-the-blank question asking us to choose the best logical connector. The answer must create the right relationship between what comes before and after the blank.
Step 3: Prethink the Answer
- Looking at our table data and passage logic, we know that pre-2006 estimates (297 km/s and 344 km/s) were considered acceptable for orbit maintenance, while the 2006 estimate (378 km/s) is deemed too high
- This means the maximum orbital velocity must be somewhere between the highest acceptable estimate and the unacceptable 2006 estimate
- The range should logically fall above the previous estimates that worked (since 344 km/s was still acceptable) but definitely below 378 km/s (which is too high according to Besla)
- So the right answer should indicate a velocity range that's higher than 344 km/s but lower than 378 km/s
above 344 km/s but below 378 km/s.
- This range (above 344 km/s but below 378 km/s) perfectly captures the logical boundary
- It's higher than the acceptable pre-2006 estimates but lower than the problematic 2006 estimate
- Matches our prethinking about where the orbital threshold must lie
above 297 km/s but below 344 km/s.
- This suggests the maximum is between 297 and 344 km/s
- But we know 344 km/s was still acceptable for orbit, so the maximum should not be lower than this
above 378 km/s.
- This suggests velocities above 378 km/s would allow orbit
- Directly contradicts Besla's finding that 378 km/s is too high for orbit maintenance
below 297 km/s.
- This suggests the maximum is below 297 km/s
- But 297 km/s was one of the acceptable pre-2006 estimates, so the maximum cannot be lower than this