The USS Grayback (SS-208), a Tambor-class submarine, was the first ship of the United States Navy to be named for the lake herring, Coregonus artedi. Having earned 8 battle stars during World War II, the USS Grayback (SS-208) was built in 1940. The submarine's first war patrol from 15 February to 10 April 1942 took her along the coast of Saipan and Guam where she had a four-day encounter with an enemy submarine; the enemy submarine fired two torpedoes at Grayback on the morning of 22 February, then continued to trail her across the Pacific. Like the USS Grampus, it had a very short fate, as it was sunk by Japanese aircraft south of Okinawa in 1944. Asbestos describes not one substance but a group of six minerals with fibrous structure which endows them with flexibility, high-tensile strength, incombustibility, and abrasion resistance. Navy veterans arehighly encouraged to undergo regular medical examinations to ensure the asbestos fibers they inhaled have not affected their lungs.