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queenisabella
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Source: Veritas Prep
Please help explain the answer explanation.
Type 1a supernovae, caused by the deterioration of matter accreted onto white dwarf stars, explode with a highly predictable brightness. Since the brightness of these explosions fades over distance in a highly predictable way, scientists have long used images measuring the brightness of type 1a supernovae to determine the distance to distant galaxies.
Which of the following discoveries, if true, would most jeopardize scientist's reliance on images of type 1a supernovae as tools for measuring distances to distant galaxies?
A)Models explaining the causes of type 1a supernovae are altered to include an updated understanding of the role played by carbon fusion.
B) Type 2 supernovae are discovered to be even more dramatically variable in their brightness than previous thought.
C) Large clouds of interstellar dust and ionized hydrogen can absorb the light emitted by type 1a supernovae.
D) Some supernovae exhibit very unusual spectral classifications and changes in brightness, and do not fit into the existing categories.
E) A new telescope is able to measure the brightness of several thousand type 1a supernovae with an unprecedented level of precision.
I wavered between the correct choice and the other one I listed below.. but after reading Veritas' explanation, still don't understand why answer C is right over answer E?
Answer Explanation:
This is a weaken question, in which the conclusion is that type 1a supernovae are an effective way of measuring distances. The reason is they have a predictable brightness that fades over distance in a predictable way. Observing and measuring this brightness then allows the distance to be reconstructed. If answer choice C, the correct answer, were true, however, external factors could create significant variations in the way that the light is observed from Earth, and the use of the brightness observations to gauge distance would seem to be unreliable. Answer choices B and D talk about other sorts of supernovae which are not the type we are considering here, and are out of scope. Answer choice A discusses the model explaining how the supernova works but says nothing about modifying the predictions of how bright the explosion is. Answer choice E does not say anything about the results of the telescope and therefore has no effect on the assumption.
Please help explain the answer explanation.
Type 1a supernovae, caused by the deterioration of matter accreted onto white dwarf stars, explode with a highly predictable brightness. Since the brightness of these explosions fades over distance in a highly predictable way, scientists have long used images measuring the brightness of type 1a supernovae to determine the distance to distant galaxies.
Which of the following discoveries, if true, would most jeopardize scientist's reliance on images of type 1a supernovae as tools for measuring distances to distant galaxies?
A)Models explaining the causes of type 1a supernovae are altered to include an updated understanding of the role played by carbon fusion.
B) Type 2 supernovae are discovered to be even more dramatically variable in their brightness than previous thought.
C) Large clouds of interstellar dust and ionized hydrogen can absorb the light emitted by type 1a supernovae.
D) Some supernovae exhibit very unusual spectral classifications and changes in brightness, and do not fit into the existing categories.
E) A new telescope is able to measure the brightness of several thousand type 1a supernovae with an unprecedented level of precision.
I wavered between the correct choice and the other one I listed below.. but after reading Veritas' explanation, still don't understand why answer C is right over answer E?
Answer Explanation:
This is a weaken question, in which the conclusion is that type 1a supernovae are an effective way of measuring distances. The reason is they have a predictable brightness that fades over distance in a predictable way. Observing and measuring this brightness then allows the distance to be reconstructed. If answer choice C, the correct answer, were true, however, external factors could create significant variations in the way that the light is observed from Earth, and the use of the brightness observations to gauge distance would seem to be unreliable. Answer choices B and D talk about other sorts of supernovae which are not the type we are considering here, and are out of scope. Answer choice A discusses the model explaining how the supernova works but says nothing about modifying the predictions of how bright the explosion is. Answer choice E does not say anything about the results of the telescope and therefore has no effect on the assumption.
- Very much better compared to B.
