Self-study
The supernova event of 1987 is interesting in that Support there is still no evidence of the neutron star that current theory says should have remained after a supernova of that size. ████ ██ ██ █████ ██ ███ ████ ████ ████ ██ ███ ████ █████████ ███████████ ████ █████████ ████ ████████ ███ ███ █████████ █████ ██ █████████ ████ ███████ █████ █████ █████ ███████ ██████ ██ █████ ██ ████████ ████ ██████████ ██ █ ███████ ████ ██████ ███████ ███████ ██████
Summarize Argument
The author concludes that current theory is wrong to claim that supernovas of certain sizes always produce neutron stars. This is because the supernova event of 1987 was of adequate size to produce a neutron star, but searches with very sensitive instruments have produced no evidence of a neutron star.
Notable Assumptions
The author assumes that because no evidence has been found yet, no neutron star exists. In other words, the author assumes that if a neutron star was produced, the searches conducted so far would have found it.
24.
Which one of the following, ██ █████ ████ ███████████ ███ █████████
a
Most supernova remnants ████ ███████████ ████ ████████ ████ █ ███████ ████ ███████
The current theory claims that supernovas of a certain size always produce neutron stars, so it's irrelevant if the theory is usually correct.
b
Sensitive astronomical instruments ████ ████████ ███████ █████ ████ ███████ ████ ████ ███ ████████ ██ ███ ████ ██████████
In other words, current instruments would likely be able to detect the neutron star in question if it existed. This strengthens the author's reliance on the searches conducted so far.
c
The supernova of ████ ███ ███ █████ ████ ██████████ ████ ████ ██ ███████ ██ █████████
Whether or not scientists had observed previous supernova events makes no difference as to whether this theory is correct. It's just irrelevant.
d
Several important features ██ ███ ████ █████████ ███ █████████ █████████ ██ ███ ███████ ███████
Even if the current theory predicts several features, it could still be wrong to claim that supernovas of a certain size always produce neutron stars. This doesn't make a difference.
e
Some neutron stars ███ █████ ██ ████ ████ ████ █████████ ██ █ █████ █████ ████ █ █████████ ██████████
The theory is about supernovas resulting in neutron stars. We don’t care how else neutron stars can come into existence, only about whether big enough supernovas always produce them.