Revelation 8:10-11 - The Third Trumpet
10 And at the sounding of the third angel, there went down from heaven a great star, burning like a flame, and it came on a third part of the rivers, and on the fountains of water. 11 And the name of the star is Wormwood: and a third part of the waters became bitter; and a number of men came to their end because of the waters, for they were made bitter.