50,000 years ago, that was the last time comet C/2022 E3 (ZTF) was close enough to the earth to be seen by earthlings.  If you believe in evolution, then that would be when Neanderthals roamed the earth.  As you might have guessed, this comet has a huge orbit around the Sun and it takes 50,000 years for it to go around the Sun once.  The plane of this comet's orbit is perpendicular to Earth's orbit and is coming in from above us.  

Click on the link below if you would like to see the comet's orbit relative to the other planets in our solar system.
Link to C/2022 E3 (ZTF) orbit
Comets are famous for their tails, as the comet gets closer to the sun, solar radiation causes materials in the comet nucleus to melt and stream away from the comet.  The Sun illuminates the comet nucleus and tail by reflected sunlight and additional illumination can result from ionization of the comet's gasses.  The comet's tail always faces away from the Sun, the solar wind and radiation pushes the dust and material always away from it, regardless of the direction the comet is going.  
Many theories, lore, superstition and cults have littered human history around these extra-terrestrial visitors.  Was the Star of Bethlehem a comet? Did a comet hit the Earth and resulting dust in the atmosphere block the sun, causing the Dinosaurs to go extinct from starvation 10 million years ago? Many of you might recall the 1997 Heaven's Gate Cult in Rancho Santa Fe when 39 men and women committed suicide so they could enter the alien spacecraft hidden behind the Hale-Bopp comet as it passed the Earth.

Acquisition:
When capturing a comet, the Astro photographer has a choice, follow the rotation of the earth (sideral, comets blurry, stars are pinpoint) or follow the orbit of the comet and compensate for the rotation of the earth (comet is clear, stars are streaks).  I wanted to get as clear a picture of this comet as possible, so I downloaded the orbital parameters of C/2022 E3 (ZTF) and loaded them into my telescope mount.  So my mount and therefore my telescope follows the orbit of the comet as well as compensates for the rotation of the earth so I can take long 10 minute exposures to get good details of the comet.  

Time Lapse
In this Episode 10, I am using 92 - 10 minute exposures in a time lapse over 5 nights to show you how the comet moved and changed over those 5 nights.  The star streaks provide an indication of how different the rotation of the earth is relative to the movement (orbit) of the comet.  The orientation is correct.  As you look at the time lapse, you are looking North.  The Earth is rotating from the West to the East, Sun rises in the East, sets in the West.  What you are seeing in the time lapse, is the rotation of the Earth is much faster than the movement of the comet.  Therefore it looks like the comet is sitting still and the stars are moving past it.  The time lapse is in an infinite loop with each 10 minute exposure in sequence for each day.  The comet has developed another tail, which is actually opposite of its large tail, "coming out the front".  You can see that in many of the images in the time lapse.  The nucleus is well defined and in many of the images you can see a very well defined narrow tail that covers over 1 degree in the sky.  Even though I used Lum, Red, Green and Blue filters on each night to take these images, I did the time lapse in monochrome, because having red, green, blue and lum images alternating would not provide any value.  The reason you see the comet fluctuate in the time lapse, is because of the different filters I used, which represent the different colors of the comet and its tails. The time lapse goes 3 frames of Lum, 3 frames of Red, 3 frames of Green and 3 frames of Blue and then repeats for all 92 frames.  The frame rate is 5 frames per second, the entire sequence takes 18 seconds and then repeats.

I captured this astronomical data using wide band (visible light) Lum, Red, Green, and Blue over 5 nights, 1/24/2023, 1/25/2023, 1/26/2023, 1/27/2023, 1/28/2023, and 1/31/2023 from my backyard.  
Lum - 34 Frames x 10 minutes unguided = 5h 40min
Red - 30 Frames x 10minutes unguided = 5h 0min 0sec
Green - 27 Frames x 10 minutes unguided = 4h 30min 0sec
Blue - 21 Frames x 10 minutes unguided = 3h 30min 0 sec
Total Imaging Time = 18h 10min

Click on the image, Top right click on full resolution to see it in more detail.