In recent years, it has become clear that large quantities of gas reside in the halos of many spiral galaxies. Whether the presence of this gas is ultimately a consequence of star formation activity in the disk, or accretion from outside of the galaxy, is not yet understood. We present new, deep HI observations of NGC 4395 as part of a continuing observational program to investigate this issue. We have detected a number of gas clouds with masses and sizes similar to Milky Way HVCs. Some of these are in regions without currently ongoing star formation, possibly indicating ongoing gas accretion.
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