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.
Evidence
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.
Conclusion
Thus, current theory is wrong in claiming that supernovas of a certain size always produce neutron stars.
Evaluate
To strengthen this argument it is helpful to think of reasons why a neutron star, if it existed, would not have been detected. Couldn’t it also be the case that the most sensitive instruments are not sensitive enough to detect the neutron star because it’s too far away? Just because the instruments are the strongest, doesn’t mean they’re strong enough.