This is the Andromeda Galaxy as photographed from my pool deck over the nights of Aug 26 and Sep 5, 2020. The photograph was taken through a William Optics Zenithstar Z61 APO Doublet refractor telescope by a ZWO ASI 1600mm Mono Chrome Pro camera, all riding on an iOptron CEM 60 center equatorial mount. I shot this image with the native focal length of 360mm. Since I was using a mono chrome camera I used wavelength filters to sort the images into wavelength groups to achieve proper color mapping.
 
The photograph is a compilation of 106 individual 3-minute exposures for a total exposure of 5.1 hours. Each picture was exposed for 3 minutes while tracking the Andromeda Galaxy across the sky. I took 21 images through a red filter, 20 images through a green filter, 20 images through a blue filter, and 45 images through a luminance filter. 
 
Our Milky Way Galaxy is part of a bunched up collection of galaxies called “The Local Group”. Our Local Group also contains the Andromeda Galaxy and several dozen other smaller galaxies, including the “Triangulum Galaxy”. Our Local Group is part of a larger collection of galaxies called the “Virgo Cluster” which in turn is part of an even larger collection of galaxies called “The Virgo Supercluster”. 
 
The Andromeda Galaxy is about 2.54 million light years from Earth in the constellation Andromeda. It is the largest galaxy in our local group. (Milky Way is a close second) The Andromeda Galaxy is approximately 300,000 light years across, is estimated to contain approximately 1 Trillion stars, and will collide with our Milky Way Galaxy in approximately 4.5 Billion years from now. (Unless they have some major medical breakthroughs, we may not be here to see it.)
 
The Andromeda Galaxy is the farthest away object that can be seen with the naked eye. To find it at night, look in between Cassiopeia and Andromeda. It will appear as a light smudge in the dark sky, about the size of an oblong quarter. The Andromeda Galaxy is visible to the Northern Hemisphere from June through February.
 
Anyhow, roughly 2.5 million years ago when there were still no humans (however homo habilis, one of the earlier links between great apes and modern humans was thriving), sabre tooth tigers and wooly mammoths were roaming, and the latest ice age and periods of glaciation were beginning, the Andromeda Galaxy sent us some photons. These are some of them. Since it takes 2.5 million years for the light to get to us from the galaxy, the photons that I caught to comprise this picture were 2.5 million years old. The had traveled for 2.5 million years through interstellar space. We see the Andromeda Galaxy in this picture the way it was 2.5 million years ago. This is the first inkling of what it means to look back in time. 
 
This image is unique in that the Andromeda Galaxy is in a constant flux of change. It will never again appear exactly as it does in this image.
 
If you like this photograph and would like to see how it was done, go to the video section on the home page to see the documentation video of how I photographed the Andromeda Galaxy.