(supernova in February 1987 rare for being visible by the naked eye)
SN 1987A is a 1987 supernova in the
Large Magellanic Cloud (LMC), about 168000 light-years away,
whose light reached Earth on February 23, 1987.
Its apparent magnitude at its brightest was +3 in May 1987
(to our view, the brightest recorded since SN 1604),
and I believe it is the only recorded supernova
visible without a telescope since the 1800s.
Neutrino detectors, including the IMB
detected bursts of neutrinos coincident with the
supernova EMR reaching Earth.
The supernova has been much studied since.
It is considered a core collapse supernova and
a portion of their study consists of the study of their
remnants. The SN 1987A remnant has more
circular symmetry than spherical, suggesting the
progenitor's stellar rotation was a factor.
Observations of the light curve have shown that the
explosion was highly asymmetric, i.e., an anisotropic explosion.
There is effort to identify a resulting neutron star,
e.g., by comparing observations to observed characteristics of
remnants where there is clearer evidence of a neutron
star.
An apparent pulsar wind nebula (PWN) has been observed.