Astr111 Photography Projects, Spring 2007

M95 Spiral Galaxy (NGC 3351), Ben Wright

The French astronomer Pierre Méchain first discovered this member of the Leo constellation in 1781, just in time for inclusion in Charles Messier's last edition of the Connoissance des Temps. Although its natural color is rather pallid when compared to some of the more spectacular nebula, I find the subtle detail and faint play of light to present an aesthetic beauty all its own. M95 is a spectacularly formed barred spiral galaxy, a form many scientists think our own galaxy, the Milky Way, resembles. Measuring about 180 (vertical) by 330 (horizontal) arc seconds across, the galaxy stretches over an area 50,000 x 70,000 light years across.

The level of faint detail this galaxy presents made preparing this image challenging. The sensitive CCD chip at the Rehobeth observatory was much better at detecting the slight gradations of light than the human eye. Ultimately, I decided to make two images with different sensitivity. In the first, I chose the fullest level of brightness possible, allowing the viewer to detect the ghost-like right arms stretching into space. For the second, I focused on the galaxy core with greater sensitivity to subtle changes in brightness. This allows the more nearly concentric rings to appear within the "heart" of the galaxy. To note in this image is the stumpy "barrel" of light crossing through the center of this galaxy. This is thought to be a column of gaseous matter flowing back into the star-forming core, helping the galaxy to continue to form new stars during its expansion.

References:

Frommert, Hartmut and Kronberg, Christine. "NGC 7293." Students for the Exploration and Development of Space. <http://www.seds.org/messier/m/m095.html>

Zombeck, Martin. "Handbook of Astronomy and Astrophysics." <http://ads.harvard.edu/books/hsaa/index.html>