This is a somewhat sad story. The brightest star in the constellation Coma Berenices is an edge-on binary system, so it’s long been predicted that we should be able to see an eclipse as one of the stars passes in front of the other from our point of view. But a few simple mistakes made a century ago (mixing up which star was which as they got close to each other) confused the prediction of when the eclipse would occur and we missed it by a couple of months.
“The next primary eclipse is in late September 2040,
a time of year which makes this system quite difficult
to observe from Earth. Cameras on distant spacecraft
could be used instead.”
h/t AAS Nova: http://aasnova.org/category/journals-digest/