Cosmic Gate is a German trance and progressive trance project made up of Claus Terhoeven (aka Nic Chagall) and formerly Stefan Bossems (DJ Bossi), both hailing from Krefeld. They are best known for their singles "Exploration of Space", "The Drums", and "The Truth." Cosmic Gate has done remixes for popular DJs including Tiësto, Armin van Buuren, and Ferry Corsten. Cosmic Gate was formed in 1999 when Terhoeven and Bossems decided to assemble a new project in the electronic music field. Their first single was "The Drums", followed by "Exploration of Space", "Mental Atmosphere" and their "Somewhere over the Rainbow" remix using samples from the film The Wizard of Oz. However, Cosmic Gate did not become well known until their single "Fire Wire" was released in the UK in 2001. Over the time of a few years, Cosmic Gate's sound developed and moved away from the harder edge trance through to their current, more subtle yet still driving energetic music style. Since their third studio album, Earth Mover, they started moving towards the Progressive Trance style. The pair have played over 1,000 gigs, typically performing between 100 and 130 nights a year. They have played at clubs such as Ministry of Sound, The Guvernment, and Privilege Ibiza. They have played alongside DJs such as Armin Van Buuren, Ferry Corsten, W&W and Hardwell. On 22 February 2026, the duo announced that Stefan was to retire from touring and would leave the group. Claus would continue under the name Cosmic Gate, including new music and live shows.