Galaxies floating in IFN - Annotated

I took this picture sometime in 2014 and though I have annotated the image in the past, but only now have I thought to post it up for others to see.

What are you looking at exactly?

Each aqua and pink coloured label is a galaxy buried deep in the IFN of Ursa Major highlighting 650 unique galaxies strewn about this image.

This 2 panel mosaic only represents a field diameter of approximately 10.2 degrees which equates to a whopping ~20 full moons across! Yes, you read that right; ~20 full moons could fit inside the diameter of this image.

How does this all work? Simple math!

The apparent size (or angular diameter is a measurement of a spherical object in the sky) of the moon is ~1800 arc seconds or 30 arc minutes (1/2 of a degree) - give a take a few arc minutes if one were to compare the apogee vs the perigee... that's a lesson for another time. So if one full moon makes up half of one degree and I have 10 degrees spanning this image that equates to 20 full moons.

Thanks for looking.

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