Messier 79 or M79 (also designated NGC 1904) is a globular cluster in the constellation Lepus. It has an apparent visual magnitude of 7.7 and its angular diameter is 8.7 arc-minutes. M79 lies at an estimated distance of 42,100 light years. The Equinox 2000 coordinates are RA= 5h 24.5m, Dec= -24° 33´ which makes M79 best seen during the winter. The Messier Winter Star Chart shows the position of all Messier objects visible during that season.
The image above shows the uncropped view of M79 through the Takahashi E-180 Astrograph (North is to right). A 3x enlargement of this image appears to the right.
This globular cluster was discovered by P. Méchain in 1780. Unlike most globular clusters located in a halo around galactic core, M79 lies far outside of it. According to Recio-Blanco et al.(2005), the distance of M79 is 45,000 light years and its diameter is 80 light years. Its estimated mass is 400,000 solar masses and it contains 7 variable stars.
Messier's Description of M79
December 17, 1780
`Nebula without star, situated below Lepus, and on the same parallel as a star of sixth magnitude: seen by M. Méchain on October 26, 1780. M. Messier looked for it on the following December 17: this nebula is beautiful; the center brilliant, the nebulosity a little diffuse; its position was determined from the star Epsilon Leporis, of fourth magnitude.'
- Object: M79
- Other Names: NGC 1904
- Object Type: globular cluster
- Object Data: Apparent Magnitude = 7.7, Angular Size = 8.7 arc-minutes
- Object Position (Equinox 2000): RA= 5h 24.5m, Dec= -24° 33´, Constellation = Lepus
- Date/Time: 2011 Nov 02 at 11:00 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: 8 x 300s, f/2.8, ISO 800
- File Name: M79-01w.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.