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.