NGC 6210 (also Turtle Nebula, Struve 5, PK 43 +37.1, Lalande 30510 and GC 4234) is a magnitude +8.8 planetary nebula located 6500 light-years away in the constellation Hercules.
It can be observed approximately 4° to the NE of the star Beta Herculis (Kornephoros). The central magnitude +12.9 white dwarf star (HD 151121, BD+24 3048), illuminates the nebula with a bluish turquoise colour (caused by ionised oxygen). Two bipolar jets of material ejected by the central star can be seen with telescopes of at least 200mm. The nebula measures about 1.6 light-years in diameter.
The planetary nebula was observed on the 22nd March 1799 and catalogued as a 8-mag star in Lalande's catalogue of 1801 as LL 30510.
The nebula was discovered by the German-Russian astronomer Friedrich Georg Wilhelm Struve using a 24.38 cm (9.6 inches) Fraunhofer refractor at the old Tartu Observatory in Dorpat in 1825.
Right ascension16h 44m 29.5s, Declination+23° 47' 59.7"
