NGC 6729 is the brightest in a complex of several reflection nebulae located between two variable stars (R CrA and T CrA) in Corona Australis. The complex is brightest near R CrA.
The three nebulae NGC 6726, 6727, and 6729 were discovered by Johann Friedrich Julius Schmidt, during his observations at Athen Observatory in 1861. Marth independently rediscovered the objects at Malta in 1864.
This is a beautiful nebular field in a heavy obscured area. It's visible with only a 2.5" telescope; with 10" aperture, NGC 6726-6727 is a fairly distinct and bright reflection nebula around stars of mag 7 and 9. NGC 6729 is faint and elongated. Its shape is oval, comet-like, and approximately 1' x 2' in size.
Measurable changes in the surface brightness of the reflection nebula associated with R CrA occur over intervals as short as 24 hours. The alterations in the appearance of the nebula NGC 6729 are apparently caused by the shadowing effects of clouds which are very close to the star, probably well within 1 AU.