A new survey of Galactic high-velocity Hi clouds

Very sensitive 21 cm. observations for high-velocity Ill clouds too faint to have been seen in other surveys have been made in more than 850 directions around the sky. Preliminary results from the survey indicate that high-velocity 21 cm HI emission is found in about one-third of all directions. Clouds with the lowest column density have kinematics similar to that of the brighter clouds, and a location on the sky which suggests that much of the faint emission comes from the outskirts of known high-velocity complexes.