A Lydian Augmented
A · B · C♯ · D♯ · E♯ · F♯ · G♯
The third mode of melodic minor, A Lydian Augmented raises both the fourth and the fifth of a major scale, so it shimmers without ever quite settling. It's the natural fit over maj7♯5 chords, and it's a favourite in film scoring for scenes that need wonder with an edge of unease. Bright, strange, and very effective in small doses.
Left-handed