Charles Messier recorded the the coordinates and a brief description of M109 in his personal copy of his catalog but it does not appear in the published catalog. It was added to the catalog (along with m103 through m110) after his death.
M109, a barred spiral, is classified SBc, it is 55 million light years distant and has a visual magnitude of 9.5.
M109 a member of the M51 group (Ursa Major cloud).