No supernova has been observed in our Milky Way galaxy since the invention of the telescope in 1608. That may be about to change.
Something strange is happening to the star Betelgeuse in the familiar constellation of Orion. Betelgeuse is a variable star that naturally varies somewhat in brightness over time. Beginning in October of 2019 it began to dim to a new historic low that has not been seen before. If you have observed the constellation Orion in the past, Betelgeuse was its second brightest star.
Because of the unusual dimming of the star some have speculated that it is about to become a supernova. If the star turns into a supernova soon it would outshine everything in the sky for several months except for the sun and maybe even the moon. Because its distance is 600 light years we are not in any danger, but it would be a truly spectacular event for all to observe. The constellation Orion would never look the same again without one of its main stars.
Betelgeuse is a red super giant star with a mass many times that of our sun. It is less than 10 million years old and is rapidly burning up its fuel. It is expected to end its existence as we know it now in about 100,000 years in a catastrophic explosion that will shed most of its mass.