Astronotes is one of Holland's leading progressive jazz groups. The ten-piece ensemble of bandleader, trombonist, and Sun Ra aficionado Joost Buis was originally founded as a Sun Ra band, but, nowadays, specializes in playing and improvising original music. The improvisational qualities of the musicians ensure that form structures and experiments with rhythm and sound are freely interpreted. It's a continuous search for the extremes in the music: on one hand the thoroughly arranged pieces, which show a great knowledge of jazz history, on the other hand free improvisations. Joost Buis turns beautiful melodies into sophisticated arrangements, which by means of a careful process of deconstruction lead to free improvisation. The trombonist led his own bands, for example the Buisband and the Buiscomplex, in an early stage of his career and played in renowned Dutch improvisation ensembles including the Willem Breuker Kollektief and the ICP Orchestra. This very interesting musician also played in several Guus Janssen operas.