63 Ophiuchi is an O-type giant star in the constellation Sagittarius, despite its name. During a 2009 survey for companions of massive stars, it was observed using speckle interferometry but no companion was found. The small parallax measurement of suggest that this extremely luminous star may be located about 3,600 light-years away. An estimate of the distance based on the strength of the Ca II line yields a more modest value of . The star lies only 0.3° north of the galactic plane. In 1983, astronomers from the Sternberg Astronomical Institute in Moscow, Russia identified a faint, shell-shaped nebula surrounding the star that was being excited by the star's energy. Named Sharpless 22, this ring-shaped nebula has a double-shell structure with an inner envelope spanning 45–50′ (9–18 pc), surrounded by a diffuse envelope some 65–80′ (14–29 pc) across. At an estimated mass loss rate of , it would take the star about to produce such a nebula from the outflow of its stellar wind. References O-type bright giants Emission-line stars Sagittarius (constellation) Durchmusterung objects Ophiuchi, 63 162978 087706 6672