M94
Messier 94 or M94 (also designated NGC 4736) is a spiral galaxy in the constellation Canes Venatici. It has an apparent visual magnitude of 8.2 and its angular diameter is 7x3 arc-minutes. M94 lies at an estimated distance of 14.5 million light years. The Equinox 2000 coordinates are RA= 12h 50.9m, Dec= +41° 08´ which makes M94 best seen during the spring. The Messier Spring Star Chart shows the position of all Messier objects visible during that season.
The image above shows the uncropped view of M94 through the Takahashi E-180 Astrograph (North is up). A 3x enlargement of this image appears to the right.
This spiral galaxy was discovered by P. Méchain in 1781. Its most outstanding features are its unusually bright core surrounded by fainter ring where active star formation is under way. According to Stoyan et al. (2010), the distance of M94 is 17.3 million light years and its diameter is 50,000 light years. Its estimated mass is 60 billion solar masses.
For more information, see the Messier Catalog as well as specific entries for M94 in Wikipedia and SEDS.
Messier's Description of M94
March 24, 1781
`Nebula without star, above the Heart of Charles [alpha Canum Venaticorum],
on the parallel of the star no. 8, of sixth magnitude of the Hunting
Dogs [Canes Venatici], according to Flamsteed: In the center it is brilliant
and the nebulosity [is] a bit diffuse. It resembles the nebula which is
below Lepus, No. 79;
but this on is more beautiful and brighter:
M. Méchain has discovered this one on March 22, 1781.'
(diam. 2.5')
Technical Details
- Object: M94
- Other Names: NGC 4736
- Object Type: spiral galaxy
- Object Data: Apparent Magnitude = 8.2, Angular Size = 7x3 arc-minutes
- Object Position (Equinox 2000): RA= 12h 50.9m, Dec= +41° 08´, Constellation = Canes Venatici
- Date/Time: 2011 Apr 25 at 07:21 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: 4 x 300s, f/2.8, ISO 800
- File Name: M94-01w.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.