NGC 6712

RA:

18:53:04.30

Dec:

-08:42:22.0

Distance from Sun:

22.5 kly

Distance from Galactic Center:

11.4 kly

Apparent Diameter:

7.4 arc min

Brightness:

8.10 mag vis

Radial Velocity:

-107.6 +/- 0.5 km/s

Diameter:

50 ly

Abs. Mag:

-7.50 Mag vis

This globular was first cataloged by William Herschel as H I.47, as he first classified it as a bright round nebula. John Herschel numbered it h 3762 in his "Cape" catalog on the ground of his observations in the 1830s, and included it in his General Catalogue of 1864 as GC 4441.

At its distance of 22,500 light-years, NGC 6712's apparent diameter of 7.4 minutes of arc corresponds to a linear extension of about 50 light-years, and its visual brightness of 8.1 mag to an absolute magnitude of -7.50, or an intrinsic luminosity of about 90,000 times that of our Sun. Its overall spectral type has been determined as F9. It is approaching us at 107.5 km/s.

The image in this page is a photograph by Martin Germano.

Cecilia Payne-Gaposchkin mentions that a dwarf nova had occurred in NGC 6712, which makes it one of three globulars where such stars were observed, the others being M5 and M30.

In 1999, ESO astronomers used the 8.2-m VLT Unit Telescope (UT1) to photograph and investigate globular cluster NGC 6712 and found evidence that this cluster is "evaporating," and has already lost its faintest stars to the Milky Way halo (De Marchi et.al. 1999).

• ESO image of NGC 6712 (ESO PR Photo 06a/99). See ESO Press Release eso9909 (04/99)

• More on NGC 6712 (SEDS Messier Database)
• Catalog of Variable Stars in NGC 6712 (Christine Clement)

References:

• Guido de Marchi et.al., 1999. A deep optical luminosity function of NGC 6712 with the VLT: Evidence for severe tidal disruption. Astronomy and Astrophysics, Vol. 343, pp. L9-L14 (03/1999) [ADS: 1999A&A...343L...9D]