While researching a topic, a student has taken the following notes:If a moon orbiting a planet comes close enough to...
GMAT Expression of Ideas : (Expression) Questions
While researching a topic, a student has taken the following notes:
- If a moon orbiting a planet comes close enough to that planet, tidal forces can cause the moon to break apart.
- In a 2022 study, researchers proposed that Saturn was once orbited by a large moon they named Chrysalis.
- Their simulations indicated that Chrysalis would likely have come very close to Saturn around 160 million years ago.
- At that distance, Chrysalis would have been broken apart by tidal forces.
- The researchers hypothesized that the resulting debris formed Saturn's rings.
The student wants to recount the sequence of events proposed by the researchers. Which choice most effectively uses relevant information from the notes to accomplish this goal?
According to researchers' simulations, two events likely occurred around 160 million years ago: first, Chrysalis came very close to Saturn, and second, debris from Saturn's rings caused the moon to break apart.
If a moon orbiting a planet (like Saturn) comes close enough to that planet, tidal forces can cause the moon to break apart.
Around 160 million years ago, a large moon (Chrysalis) came close enough to Saturn that tidal forces broke the moon apart; its debris then formed the planet's rings.
First, researchers proposed that Saturn was orbited by a large moon (Chrysalis); next, they conducted simulations; and, finally, they formed a hypothesis.
Step 1: Decode and Map the Passage
Part A: Create Passage Analysis Table
| Text from Passage | Analysis |
|---|---|
| "If a moon orbiting a planet comes close enough to that planet, tidal forces can cause the moon to break apart." |
|
| "In a 2022 study, researchers proposed that Saturn was once orbited by a large moon they named Chrysalis." |
|
| "Their simulations indicated that Chrysalis would likely have come very close to Saturn around 160 million years ago." |
|
| "At that distance, Chrysalis would have been broken apart by tidal forces." |
|
| "The researchers hypothesized that the resulting debris formed Saturn's rings." |
|
Part B: Provide Passage Architecture & Core Elements
Main Point: Researchers propose that Saturn's rings formed from debris when tidal forces broke apart a moon called Chrysalis 160 million years ago.
Argument Flow: The notes start with a general scientific principle about tidal forces, then present a specific application where researchers propose Saturn once had a moon that came too close, got broken apart by those same tidal forces, and created the debris that became Saturn's rings.
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
- Based on our analysis, the sequence of events the researchers proposed would be:
- First, Chrysalis (the moon) came very close to Saturn around 160 million years ago
- Second, when it got that close, tidal forces broke the moon apart
- Third, the debris from that breakup formed Saturn's rings
- The right answer should present these three events in chronological order, showing the cause-and-effect chain from the moon's approach to the formation of the rings
According to researchers' simulations, two events likely occurred around 160 million years ago: first, Chrysalis came very close to Saturn, and second, debris from Saturn's rings caused the moon to break apart.
✗ Incorrect
- Gets the sequence completely backwards
- Claims "debris from Saturn's rings caused the moon to break apart" when the researchers actually proposed the opposite - the broken moon created the rings
- What trap this represents: This choice reverses cause and effect, which is a common error when students don't carefully track the logical flow
If a moon orbiting a planet (like Saturn) comes close enough to that planet, tidal forces can cause the moon to break apart.
✗ Incorrect
- Only states the general principle about tidal forces
- Doesn't recount any sequence of specific events about Chrysalis and Saturn
- Fails to address what the researchers actually proposed happened
Around 160 million years ago, a large moon (Chrysalis) came close enough to Saturn that tidal forces broke the moon apart; its debris then formed the planet's rings.
✓ Correct
- Presents the complete sequence in correct chronological order
- Shows the cause-and-effect chain: Chrysalis came close → tidal forces broke it apart → debris formed rings
- Includes the timing (160 million years ago) and matches our prethinking perfectly
First, researchers proposed that Saturn was orbited by a large moon (Chrysalis); next, they conducted simulations; and, finally, they formed a hypothesis.
✗ Incorrect
- Describes the researchers' process (proposed, conducted simulations, formed hypothesis)
- Doesn't recount the sequence of events they think actually happened to Chrysalis
- What trap this represents: This choice confuses the research process with the historical events the research proposed