head in the clouds

absent absorbed abstracted airheaded bemused careless distracted distrait dreaming dreamy engrossed faraway forgetful goofing off heedless inattentive inconscient lost mooning moony oblivious out to lunch pipe dreaming preoccupied remote removed scatterbrained space cadet spacey unaware of events unconscious unheeding unmindful unobservant unthinking withdrawn woolgathering

alert attentive aware