Then the fourth angel blew his trumpet. A third of the sun was struck, and a third of the moon, and a third of the stars, so that their light lost a third of its brightness; there was no light during a third of the day and a third of the night also. 1
References for Revelation 8:12
Then I looked, and I heard an eagle that was flying high in the air say in a loud voice, "O horror! horror! How horrible it will be for all who live on earth when the sound comes from the trumpets that the other three angels must blow!"