The supernova event of 1987 is interesting in that there is still no

Question

The supernova event of 1987 is interesting in that there is still no evidence of the neutron star that current theory says should have remained after a supernova of that size. This is in spite of the fact that many of the most sensitive instruments ever developed have searched for the tell-tale pulse of radiation that neutron stars emit. Thus, current theory is wrong in claiming that supernovas of a certain size always produce neutron stars.

Which one of the following, if true, most strengthens the argument?

(A) Most supernova remnants that astronomers have detected have a neutron star nearby.

(B) Sensitive astronomical instruments have detected neutron stars much farther away than the location of the 1987 supernova.

(C) The supernova of 1987 was the first that scientists were able to observe in progress.

(D) Several important features of the 1987 supernova are correctly predicted by the current theory.

(E) Some neutron stars are known to have come into existence by a cause other than a supernova explosion.

Bunuel · Accepted Answer

EXPLANATION FROM POWER SCORE

Strengthen. The correct answer choice is (B)

Current theory regarding supernovas states that when there is a supernova event the size of the one that occurred in 1987, a neutron star should have remained afterward. Yet there is still no evidence of any such neutron star or of the pulse of radiation normally associated with such an event, in spite of searches conducted using some of the most sensitive instruments ever developed. The writer then concludes that current theory is wrong with regard to the assertion that supernovas of a certain size always produce neutron stars.

This stimulus presents the following conditional relationships: If there is a supernova, there is a neutron star, and if there is a neutron star, there is generally a pulse of radiation:

Supernova --> neutron star --> pulse of radiation

We are asked which of the answer choices most strengthens the argument, the conclusion of which is that current theory is wrong with regard to supernovas and neutron stars.

Answer choice (A): This answer choice lends support to  current  theory, which would actually weaken the author’s conclusion that current theory must be wrong.

Answer choice (B): This is the correct answer choice. If these instruments have detected neutron stars at a greater distance than the 1987 supernova, this would strengthen the case that these instruments would detect a neutron star that resulted from the 1987 supernova, if such a star existed. This lends support to the author’s assertion that current theory must be wrong.

Answer choice (C): This statement neither strengthens nor weakens the writer’s conclusion that the current theory is wrong.

Answer choice (D): Since this answer choice lends credibility to current theory, this weakens the writer’s conclusion that current theory must be wrong.

Answer choice (E): None of this explains the absence of the neutron star in this instance. This information is irrelevant to the writer’s argument regarding current theory. Because it certainly does not strengthen the author’s conclusion, this answer choice should be eliminated.

Nidzo · Answer

(A) Most supernova remnants that astronomers have detected have a neutron star nearby.
 This answer choice leaves many holes. Are there one's which they haven't been able to detect but which do have neutron stars? In which case the theory is true.

(B) Sensitive astronomical instruments have detected neutron stars much farther away than the location of the 1987 supernova.
 We now know that there is no possible chance that the astronomical instruments are at fault and not picking up the neutron star if they could pick up neutron stars from a lot further away.

(C) The supernova of 1987 was the first that scientists were able to observe in progress.
 Does not offer any information as to why in theory there should be a neutron star but there isn't.

(D) Several important features of the 1987 supernova are correctly predicted by the current theory.
 This would weaken the argument. This choice leaves a possibility of the neutron existing but merely not being detected by instruments.

(E) Some neutron stars are known to have come into existence by a cause other than a supernova explosion.
 While other causes may exist, the focus here is on neutron stars being created after a supernova explosion and why in this instance one wasn't.

Answer B

Bunuel · Answer

EXPLANATION FROM Fox LSAT

The problem with the logic here is that it assumes that if the neutron star were there, “The most sensitive instruments ever developed,” would have found it. But what if our instruments just aren’t good enough? To strengthen this argument, I’d love to see an answer choice that says something about the bad-assedness of our current instruments, something like, “Current instruments are plenty powerful enough to have detected the neutron star if it actually existed.”

A) Not what we’re looking for.

B) This is close, because it suggests that the instruments we have are powerful enough to detect neutrons “much farther away” than the one we’re looking for from 1987. So this is our answer unless something else jumps out at us.

C) Not relevant.

D) So what.

E) Not relevant.

Our answer is B. This was an example of a question that really requires you to attack it before you try to strengthen it. The correct answer strengthens the argument by plugging up a potential point of weakness in the argument. If you can find a hole in your argument, then you know what kind of evidence you need to strengthen it. All the other answers are simply irrelevant.

dine5207 · Answer

Explanation from LSAC :
This question asks you to identify the response that most strengthens the argument. The argument concludes that “current theory is wrong in claiming that supernovas of a certain size always produce neutron stars” based on the observation that no evidence has been found of a neutron star left behind by the supernova event of 1987. However, the failure to find evidence of the predicted neutron star does not necessarily indicate that such evidence does not exist. It may instead indicate that the instruments used to search for the evidence are not powerful enough to detect a neutron star in the area where the 1987 supernova event occurred. The argument would thus be strengthened if there was evidence that the search instruments used would in fact be capable of finding the predicted neutron star if that star existed.

Response (B) provides such evidence. If “sensitive astronomical instruments have detected neutron stars much farther away than the location of the 1987 supernova,” then it is less likely that the predicted neutron star is outside the detection range of “the most sensitive instruments ever developed.” Thus, (B) is the correct response.

Response (A) reports that most supernova remnants that astronomers have detected have a neutron star nearby. Since (A) gives no information about the size of the supernovas that produced these remnants, it is possible that all of the remnants detected to date are consistent with the current theory’s claim that supernovas of a certain size always produce neutron stars. (A), therefore, lends no support to the argument that the current theory is wrong in this claim.

Response (C) reports that the supernova of 1987 was the first supernova that scientists were able to observe in progress. This information has no direct bearing on the question of whether this event produced a neutron star and thus cannot be used to strengthen the argument that the current theory is wrong.

VerbalBot · Answer

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The supernova event of 1987 is interesting in that there is still no

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