Astronaut on board ISS captured the ship contrails near Aleutian Islands. The contrails are presumably the tracks of ships that connect Japan or China and Canada and/or the U.S.
Ship tracks are clouds that form around the exhaust released by ships into the still ocean air. Water molecules collect around the tiny particles (aerosols) from exhaust to form a cloud seed. More and more water accumulates on the seed until a visible cloud is formed. In the case of ship tracks, the cloud seeds are stretched over a long narrow path where the wind has blown the ship’s exhaust, so the resulting clouds resemble long strings over the ocean.
Reference: Ship Tracks, Aleutian Islands (NASA Earth Observatory)
See earthview photo gallery: LiVEARTH