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?
Most supernova remnants that astronomers have detected have a neutron star nearby.
Sensitive astronomical instruments have detected neutron stars much farther away than the location of the 1987 supernova.
The supernova of 1987 was the first that scientists were able to observe in progress.
Several important features of the 1987 supernova are correctly predicted by the current theory.
Some neutron stars are known to have come into existence by a cause other than a supernova explosion.
Explanation for Question 4
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.
Response (D) asserts that several important features of the 1987 supernova are correctly predicted by the current theory. This bolsters the support for the current theory and would thus, if anything, weaken the argument that the current theory is wrong.
Response (E) reports that not all neutron stars are the products of supernova events. Since this information pertains to neutron stars that were not produced by supernovas, it is irrelevant to the question of whether all supernovas of a certain size produce neutron stars, as the current theory claims. Hence, (E) lends no support to the argument.
This was a difficult question, based on the number of test takers who answered it correctly when it appeared on the LSAT.