The sky protects the earth from the lethal rays of the sun. It also acts like a blanket to protect it from the freezing cold of space. The sky also protects life on earth through heat retention (greenhouse effect)
Dua for Protection from all serious and life-threatening illnesses: "Allah humma inni AA-oothu bika minal junoo-ni wal juthaami wal barasi wa sayyi-il asqaam." Oh Allah, I seek Your refuge from insanity, mutilation, leprosy and from all serious illnesses.