This composite image shows the progression of the Lunar eclipse from 3:27-4:02 am EST on November 19, 2021 with Earth's Umbra represented by the grey circle. The direction of motion of the Moon is from the right to the left.
This work was inspired by the APOD on 11/25/2021 (see:
https://apod.nasa.gov/apod/ap211125.html). I was blown away by this image as both a work of art and a demonstration of the scientific principles underlying an eclipse. The image beautifully shows how the motion of the Moon along its orbital path through the Earth's shadow produces the progression of the shadowed region on the Moon.
I didn't plan for this ahead of time, but was fortunate to capture four images spaced about 10 minutes apart leading up to maximum eclipse. I opened these four images as separate layers in GIMP to align them. I generated the circle representing the Earth's umbra in Paint3D and opened that as another layer in GIMP. I then scaled the size of the circle to the correct image scale:
Moon (diameter): 0.49 degrees = 1770 arcsec / 1900 pixels = 0.93 arcsec/px
Earth's umbra (diameter): 1.287 degrees = 4600 arcsec / (0.93 arcsec/px) = 5000 px
Finally, I aligned the images of the Moon with the shadow boundary along the circumference of the circle representing the umbra. Oh boy was I happy with the result with the images aligned to the umbral shadow boundary having close to equal spacing (each shot about 10 minutes apart) showing straight line motion of the Moon.
Imaged with WO GT81 at F12 using a 2x Celestron barlow (478x2=~956 mm focal length) and Nikon D750 full frame DSLR. Four single shots at ISO1600 with a exposures ranging from 1 - 2 seconds.
Image 1: 3:27 am EST
Image 2: 3:39 am EST
Image 3: 3:51 am EST
Image 4: 4:02 am EST
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