Messier 14 or M14 (also designated NGC 6402) is a globular cluster in the constellation Ophiuchus. It has an apparent visual magnitude of 7.6 and its angular diameter is 11.7 arc-minutes. M14 lies at an estimated distance of 29,000 light years. The Equinox 2000 coordinates are RA= 17h 37.6m, Dec= -03° 15´ which makes M14 best seen during the summer. The Messier Summer Star Chart shows the position of all Messier objects visible during that season.
The image above shows the uncropped view of M14 through the Takahashi E-180 Astrograph (North is up). A 3x enlargement of this image appears to the right.
This globular cluster was discovered by Messier in 1764. According to Recio-Blanco et al.(2005), the distance of M14 is 55,620 light years and its diameter is 180 light years. Its estimated mass is 1.2 million solar masses and it contains 68 variable stars.
Messier's Description of M14
June 1, 1764
`Nebula without star, discovered in the garb which dresses the right arm of Ophiuchus, and situated on the parallel of Zeta of Serpens: this nebula is not large, its light is faint, one can see it nevertheless with an simple refractor of 3.5 feet; it is round, near it is a small [faint] star of the nineth magnitude; its position has been determined by comparing it with Gamma of Ophiuchus, and M. Messier has reported its position on the Chart of the Comet of 1769. Memoirs de l'Academy, year 1775, plate IX. Reviewed on March 22, 1781.' (diam. 7')
- Object: M14
- Other Names: NGC 6402
- Object Type: globular cluster
- Object Data: Apparent Magnitude = 7.6, Angular Size = 11.7 arc-minutes
- Object Position (Equinox 2000): RA= 17h 37.6m, Dec= -03° 15´, Constellation = Ophiuchus
- Date/Time: 2011 Apr 12 at 10:08 UTC
- Location: Bifrost Astronomical Observatory, Portal, AZ
- Mount: Astro-Physics 1200GTO
- Telescope: Takahashi Epsilon 180 Hyperbolic Astrograph
- Camera: Canon EOS 550D (Rebel T2i) (modified with a Baader UV/IR filter)
- Field of View: 1.70° x 2.56° at 1.7 arc-sec/pixel (web version: 10.0 arc-sec/pixel)
- Exposure: 2 x 300s, f/2.8, ISO 800
- File Name: M14-01w.jpg
- Processing (Adobe Camera Raw): Graduated Filter, Vignetting Correction, Noise Reduction, White Balance, Curves
- Processing (Photoshop CS5): Average Images, Curves, Noise Reduction
- Original Image Size: 3454 × 5179 pixels (17.9 MP); 11.5" x 17.3" @ 300 dpi
- Rights: Copyright 2011 by Fred Espenak. All Rights Reserved. See: Image Licensing.