While looking up at the stars I wondered, what are the odds that some of them are already dead. I did some research and found a very interesting article here. It states that the odds are rather small, so it is not like about 50% of the stars we see are already dead.
But I still wonder if there is an example of a star we know to be already gone, while it is still visible on earth.
As far as I know, the only way to find out is to watch the stars light. So if the light "goes out", we know the star has been gone for quite some time. Assuming this to be fact, I would have to conclude that such an example does not (and cannot) exist.
Is this true? Or is there in fact a star that is already dead that we know of, which can be seen in the sky?
PS: By "seeing the star" I am talking about a star that looks just like any other star in the night sky (not, for instance, a visible supernova).
Edit: If there is such a star, how did we find out it is already gone?