M83 - Southern Pinwheel
Messier 83 or M83 (also designated NGC 5236) is a spiral galaxy in the constellation Hydra. It has an apparent visual magnitude of 7.6 and its angular diameter is 11x10 arc-minutes. M83 lies at an estimated distance of 15 million light years. The Equinox 2000 coordinates are RA= 13h 37m, Dec= -29° 52´ which makes M83 best seen during the spring. The Messier Spring Star Chart shows the position of all Messier objects visible during that season. As one of the more famous objects in the Messier Catalog, it is commonly known as the Southern Pinwheel Galaxy.
The image above shows the uncropped view of M83 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 N. L. Lacaille in 1752. The Southern Pinwheel Galaxy is the southernmost galaxy in the Messier Catalog. It is well known for its distinct spiral arms. According to Stoyan et al. (2010), the distance of M83 is 14.7 million light years and its diameter is 55,000 light years.
Messier's Description of M83
February 17, 1781
`Nebula without star, near the head of Centaurus: it appears as a faint and even glow, but it is difficult to see in the telescope, as the least light to illuminate the micrometer wires makes it disappear. One is only able with the greatest concentration to see it at all: it forms a triangle with two stars estimated of sixth and seventh magnitude: [its position was] determined from the stars i, k and h in the head of Centaurus: M. de la Caille has already determined this nebula.'
- Object: M83
- Other Names: NGC 5236, Southern Pinwheel Galaxy
- Object Type: spiral galaxy
- Object Data: Apparent Magnitude = 7.6, Angular Size = 11x10 arc-minutes
- Object Position (Equinox 2000): RA= 13h 37m, Dec= -29° 52´, Constellation = Hydra
- Date/Time: 2011 Apr 04 at 06:27 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: M83-01w.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.