two planets

Two planets, cruising in the Universe, come pretty close to each other. 
"How's it going ?" asks one and the other, just shruggs his shoulders and says: "Oh, not so good!"
"What's troubling you?" asks the first planet .
Ach, sighs the other, "I have a severe case of Mankind...."
"Don't worry", soothes the first: "This doesn't last long."