According to the BBC the lunar eclipse on July 27th/28th 2018 is the "longest this century".
Longest isn't a very good way of describing things, since it's a relative measure without reference to actual numbers, and implies it's somehow longer in some way that might actually matter in a practical way.
How much longer is this lunar eclipse than:
- An "average" lunar eclipse?
- The next lunar eclipse?
- The shortest lunar eclipse this century?
- The 2nd longest lunar eclipse this century?
(Feel free to add in any questions/answers I might have missed that may explain "longest" in a better context.)