Mastodon is an American heavy metal band from Atlanta, Georgia, formed in early 2000 and composed of bassist/vocalist Troy Sanders, guitarist/vocalist Brent Hinds, guitarist Bill Kelliher and drummer/vocalist Brann Dailor. The band is known for their unique "sludgy" sound, mixing clean and distortion-heavy instrumental work and often involving intricate instrumental passages and use of vocal harmonies.
Crack the Skye is the fourth studio album of the band, released on March 24, 2009 through Reprise Records.The record would tell a story dealing variously with the art aesthetics of Tsarist Russia, astral travel, out of body experiences and Stephen Hawking's theories on wormholes.