"Physical beings may sense when an astral form passes through their aura. Make a Perception + Intuition (4) [Mental] Test - you receive a +2 dice pool bonus if you're Awakened. If the test is successful, the character feels slightly breathless, and they experience a chill or tingling sensation from the passing of the astral form." p.314.
Is this test (and Skill) useful if the astral form is moving at 1670 m. per second (running), 33 m. per second (walking) on by, or materializing exactly in your place, in order to attempt to Engulf you on its next Combat Turn?