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Astronomical Observatory: Cool Images

Astr111 Photography Projects, Spring 2007

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M78, Aaron Gonzalez



The objects of interest are centered around the top left region of the picture. These are a cluster of stars emitting red crowns of light around the edges with a white center, while there is a blue cloud of light which is being reflected by some space dust. The dust creating this blue reflection is located mostly behind these stars. Other areas in the blue dust cloud which appear darker are actually dust which is infront of the stars. This catches the light instead of reflecting it thus its daker shading. the red shading near the top is actually the gasses emmitting color.. This type of star cluster is categorized as a diffuse reflection nebula. This particular diffuse reflection nebula (M78) is the brightest in the sky. It was discovered by Pierre Méchain in early 1780, and is considered part of the Orion complex which belongs to the Orion Nebula (known for its large collection of dust and gasses). Its linear size is approximately 1.86 light years.


The diffuse reflection nebula (m78) is scientifically similar to the Earth's sky during the day. At night we are able to see the stars because the sky is not reflecting the blue in the sun's ray. This reflection of light is a result of the particular composition of the Earth's gases which spit out the color blue much better than other colors. In the same way, M78 has a particular composition of dust which reflect the color blue from the cluster better than any other color, which is why we see a blue toned cloud around this star cluster. This collection of gasses and dust is also an indication that this star cluster is relatively young. Other clusters which are relatively older have very little gasses and dust because the gasses and dust have had plenty of time to disperse.


Right Ascension (J2000) 05:46:42
Declination (J2000) +00:03:10
Filters used blue(B), green(V), red(R), and clear(C)
Exposure time per filter 5x60 seconds in C, 300 seconds in BVR
Date observed

March 07, 2007 (C)
March 07, 2007 (BVR)




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