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Zorluk: OrtaComparing and Contrasting Models

### Models of Martian Atmospheric Loss

Scientists agree that Mars once possessed a much thicker, warmer carbon dioxide (CO2CO_2) atmosphere than it does today. However, they disagree on the primary mechanism responsible for the loss of this atmosphere.

Model 1
Mars lost its atmosphere primarily through *solar wind stripping*. Early in its history, Mars had a liquid core that generated a strong global magnetic field, protecting the atmosphere. Approximately 4 billion years ago, the core cooled, and the magnetic field decayed. Without magnetic protection, high-energy particles from the solar wind directly struck the upper atmosphere. These particles transferred energy to gaseous molecules (primarily CO2CO_2 and H2OH_2O), accelerating them past Mars's escape velocity. This continuous stripping depleted the atmosphere over hundreds of millions of years.

Model 2
Mars lost its atmosphere primarily through *impact erosion* during the Late Heavy Bombardment, a period of intense asteroid and comet impacts between 4.1 and 3.8 billion years ago. When large impactors struck Mars, they produced massive vapor plumes that expanded faster than Mars's escape velocity, driving large portions of the overlying atmosphere into space. Because Mars has a relatively low gravitational acceleration (3.71 m/s23.71\text{ m/s}^2), these explosive impacts were highly efficient at ejecting gases. In contrast, the solar wind has a negligible long-term effect because the planet's gravity is strong enough to retain molecules energized solely by solar particles.

According to Model 1 and Model 2, which of the following statements describes a point of disagreement between the two models regarding the mechanism of atmospheric loss on Mars?

  1. A
    Model 1 proposes that atmospheric loss occurred primarily during the Late Heavy Bombardment, whereas Model 2 proposes that atmospheric loss occurred continuously after the decay of Mars's magnetic field.
  2. B
    Model 1 suggests that vapor plumes from asteroid impacts directly drove gases into space, whereas Model 2 suggests that gaseous molecules were stripped directly by solar particles.
  3. Model 1 asserts that high-energy solar wind particles drove atmospheric gases past escape velocity, whereas Model 2 asserts that solar wind particles had a negligible long-term effect on atmospheric depletion.Cevap
  4. D
    Model 1 claims that Mars's low gravity was the primary factor allowing solar wind particles to strip the atmosphere, whereas Model 2 claims that a liquid core protected the atmosphere during impacts.

Cevap

Model 1 asserts that high-energy solar wind particles drove atmospheric gases past escape velocity, whereas Model 2 asserts that solar wind particles had a negligible long-term effect on atmospheric depletion.
The correct answer states that Model 1 asserts high-energy solar wind particles drove atmospheric gases past escape velocity, whereas Model 2 asserts that solar wind particles had a negligible long-term effect on atmospheric depletion. This accurately reflects that Model 1 attributes atmospheric loss directly to the energy transferred from solar wind particles, while Model 2 discounts solar wind stripping, arguing that Mars's gravity is strong enough to retain molecules energized solely by solar particles.

Adım Adım Çözüm

1
Analyze Model 1's stance on solar wind and atmospheric loss.
Model 1 states that solar wind particles directly struck the upper atmosphere and transferred energy to gaseous molecules, accelerating them past escape velocity and depleting the atmosphere.
To identify how Model 1 views the role of the solar wind.
2
Analyze Model 2's stance on solar wind and atmospheric loss.
Model 2 states that the solar wind has a negligible long-term effect on atmospheric depletion because Mars's gravity is strong enough to retain those molecules.
To identify how Model 2 views the role of the solar wind and compare it to Model 1.
3
Compare the analyzed stances against the given choices to find the statement that represents a point of disagreement.
The statement detailing Model 1's claim about solar wind stripping and Model 2's counter-claim that solar wind has a negligible effect matches the differences described in the passage.
To determine the correct choice demonstrating a clear point of disagreement.

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Comparing and Contrasting Models
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Comparing and Contrasting Models

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