Up next from last Friday is Messier 44, the Beehive Cluster. An open cluster of stars that lies 5-600 light years away and is about 600 million years old.

This cluster caught my eye as I was gazing up at Mars one night from Sugar Grove. It was a naked eye fuzzy patch, one of those that you only see when you look away from it. Look right at it, and it disappears. Hence is the construction of our eyes, and one of the most important concepts about visual astronomical observation: averted vision. Human eyes can see well in color, but only in brighter light because of the cones concentrated in the center of our field of vision. Away from the center of vision, the more light-sensitive cones are more numerous, but less sensitive to color. Therefore, when you look away from a dim object, it tends to become more apparent, and when you look right at it, it disappears. This concept is well demonstrated when observing the Blinking Planetary nebula in Cygus.

But, I digress.

Image Stats:
Canon 300mm EF-L @ f/4
Canon XSi @ ISO 800, unmodified
38 X 30 second exposures with auto dark subtraction (19 minutes integration time)
CGE mount, unguided.