San Pedro de Atacama Celestial Explorations

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Comet C/2021 A1 Leonard

Comet C/2021 A1 Leonard

This page contains various versions of images taken by Alain Maury and processed by Georges Attard and him of comet Leonard in December 2021.

Unless mentioned otherwise, the images were taken with a Celestron RASA11" and a zwo 6200MM (monochrome) CMOS camera.

To give a bit more detail, we wanted not to saturate the nucleus of the comet, so we used very short exposures (5 seconds), leading in the more or less two hours of visibility of the comet to about 1000 images of 110 megabytes to be processed each following day. Using the prism software (which I use for everything astronomical) I wrote a script to preprocess, recenter, bin by 2, and make a window around the comet which processes the 1000 images in about 2 hours and a half on a I9 machine. Then Georges takes the images make some processing on them and creates the animation which are below.

While it doesn't show, we had to degrade the quality of the images and had to do median stacks of individual images in order to remove the tracks left by tons of f#@~~ ing artificial satellites

Images from December 27th :


2 megabyte gif animation :


5 megabyte animation :


Original size animation (57 Mb, be patient) can be found here

Here is another version of the same animation, but the processing was done normally, leaving all the trails of all the satellites which crossed the field during the observations. Now imagine that in ten years, when we will have such a comet (low on the horizon at the beginning of the night, or the end of the night) with about ten times more satellites.

Images from December 28th

6.7Mb animation


The original size animation (55 Mb) is here

Images from December 29th

10.5Mb animation, seems like the comet took a day off.


the original size animation (65Mb) is here

Images from December 30th

10Mb animation


Link to the full size (61 Mb) movie is here

More images to come...

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