Abstract: A post-avalanche upward indicating aid device is provided. The device includes a body, an illumination source and an attachment means. The body has a generally central cavity which is partially filled with a liquid and closed or sealed. The illumination source enables the liquid in the cavity to be observed in darkness and an attachment point is provided so that the device can be securely fastened to or carried by a user.The aid device incorporates the effect of gravity on a liquid contained in a closed, partially liquid-filled cavity. That is, gravity draws the liquid in the partially liquid-filled cavity in a downward direction so that the partially-empty area or bubble in the cavity will always tend toward a position above the liquid. Thus, by observing the location of the bubble in the central cavity, the device provides an automatic, immediate and readily visible indication of the generally upward direction to a victim buried in snow after being caught in an avalanche.