M78
Messier 78 or M78 (also designated NGC 2068) is a diffuse nebula in the constellation Orion. It has an apparent visual magnitude of 8.3 and its angular diameter is 8x6 arc-minutes. M78 lies at an estimated distance of 1600 light years. The Equinox 2000 coordinates are RA= 5h 46.7m, Dec= +00° 03´ which makes M78 best seen during the winter. The Messier Winter Star Chart shows the position of all Messier objects visible during that season.
This diffuse nebula was discovered by P. Méchain in 1780. M78 is part of the much larger Orion Molecular Cloud Complex.This immense region also includes the Great Orion Nebula M42, M43 and the Horsehead Nebula located south of Zeta Orionis (Alnitak), the easternmost star in the Belt of Orion. According to Stoyan et al. (2010), the distance of M78 is 1300 light years and its diameter is 3 light years.
For more information, see the Messier Catalog as well as specific entries for M78 in Wikipedia and SEDS.
Messier's Description of M78
December 17, 1780
`Cluster of stars, with much nebulosity in Orion and on the same parallel as the star Delta in the belt, which has served to determine its position; the cluster follows [is east of] the star on the hour wire at 3d 41', and the cluster is above [north of] the star by 27'7". M. Méchain had seen this cluster at the beginning of 1780, and reported: "On the left side of Orion [Glyn Jones has, erroneously, the right]; 2 to 3 minutes in diameter, one can see two fairly bright nuclei, surrounded by nebulosity".' (diam. 3')
Technical Details
- Object: M78
- Other Names: NGC 2068
- Object Type: diffuse nebula
- Object Data: Apparent Magnitude = 8.3, Angular Size = 8x6 arc-minutes
- Object Position (Equinox 2000): RA= 5h 46.7m, Dec= +00° 03´, Constellation = Orion
- Date: 2019 Jan-Mar on multiple nights
- Location: NSW, Australia
- Data Acquisition: Calibrated sub-frames from Martin Pugh
- Telescope: Astro-Physics 305mm F/3.8 Riccardi-Honders Astrograph (FL = 1160mm)
- Camera: SBIG STXL-16200 with 7-position Filter Wheel
- Mount: Software Bisque Paramount MEII
- Sub-Exposures: Astrodon LRGB GenII Filters
- L: 12 x 20 min = 240 min
- R: 8 x 20 min = 160 min
- G: 8 x 20 min = 160 min
- B: 7 x 20 min = 140 min - Total Exposure: 11h 40m
- File Name: M78-RH21-A01w.jpg
- Field of View: 65.2' x 97.8' at 1.07 arc-sec/pixel
- Original Image Size: 3630 x 4540 pixels (16.5 MP); 12.1" x 15.1" @ 300 dpi
- Image Processing: Fred Espenak
- Deep Sky Stacker: Registration, Stacking
- Maxim DL: Log Stretch,
- Adobe Camera Raw: Noise Reduction
- Photoshop CC: Curves, Levels
- Topaz Labs: Sharpen AI - Copyright: Fred Espenak