Massive breakthrough album for Tangerine Dream on Virgin Records at around the same time as Mike Oldfield’s Tubular Bells. This is the first of theirs to not feel entirely harsh and spacey and have a little semblance of softness and melody. Side-long opener title track is a mini-masterpiece, very ambient, wonderful, proggy, psycheldic and serene before it glides into a siren-blaring space station meltdown situation. Second side is sketchier and not quite as magisterial but overall still a class work.