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Astr110 Photography Projects, Spring 2010

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M100 , Jason Folkert


M100 is a spiral galaxy, very similar to our very own Milky Way. The galaxy has approximately 100 billion stars composing two large arms of blue-tinted arms that come off of its center nucleus and several ones that are more faint. A galaxy is a group of stars that all revolve around a center nucleus. M100 is found in the constellation Coma Berenices. It was discovered in March of 1781 by Pierre Mechain and his friend, Charles Messier obtained its position the next month. M100 has a magnitude of 9.3 and its distance is around 56 million light-years from earth.

The tilt of M100 compared to earth is one such that the galaxy is facing us head-on. This allows us to take photos of it which displays its spiral arms. In the photo above, the usual blue-tinted arms are more bluish-gray in color. The image of M100 appears to show a galaxy that is almost perfect symmetrical in its shape. However, in detailed photos, the lower half appears to be brighter due to the formation of new stars in that area. The angular size of the photo is 4.18 arc minutes and the linear size is calculated to be 68000 light-years based on the photo. The actual angular size of M100 has been found to be 7' x 6'. This is off from the 4.18' my photo showed so there must be portions of the M100 galaxy to faint to show up in the photo and taken into account for the angular size.

Bonnell Jerry and Robert Nemiroff. "M100: A Grand Design" NASA. <http://antwrp.gsfc.nasa.gov/apod/ap980606.html>

Frommert, Hartmut and Kronberg, Christine. "Messier 100 (NGC 4321)." Students for the Exploration and Development of Space. <http://www.seds.org/messier/m/m100.html>

Right Ascension (J2000) 12:22:55
Declination (J2000) 15:49:23
Filters used blue(B), green(V), red(R), and clear(C)
Exposure time per filter 300 seconds in BVRC
Date observed

March 3, 2010 at 00:28:48 EST (BVRC)