Urmas Sisask (9 September 1960 – 17 December 2022) was an Estonian composer.
[1] Sisask was born in Rapla on 9 September 1960.
Based on the trajectories of the planets in the Solar System, he created the "planetal scale", a mode consisting of the pitches C#, D, F#, G#, and A.
[1] Sisask was a Roman Catholic, and much of what he composed was sacred music.
His younger sister is singer and actress Siiri Sisask.