Messier 19 (also known as M19 or NGC 6273) is a globular cluster in the constellation Ophiuchus. It was discovered by Charles Messier in 1764 and added to his catalog of comet-like objects that same year.

M19 is the most oblate known globular cluster. It is at a distance of about 28,000 light-years from the Solar System, and quite near to the Galactic Center, only about 5,200 light-years away.

M19 is easily found about 8 deg east of Antares in the Milky Way, and is visible as a small globular glow, with its ellipticity easily notable. It is quite easily resolved.

A further globular cluster, NGC 6293, of mag 8.4 and 1.9' diameter is located 1.5 deg to the ESE, and another one, NGC 6284, of mag 9.5 and 1.5' diameter, 1.6 deg to the NNE