File talk:Comet 2020 F3-skyview.png

Source specification

Tomruen , could you please provide a precise source?
-If you picked the file from the internet - please provide a specific URL.
-If you digitized it yourself, then please state so and therefore please specify the book you took as source, e.g. giving the ISBN number. If possible add pagenumber.
-If you made a diagram yourself - please provide your Template or data-source
-If there is a sourcecode used in generation, it is highly appreciated to provide it.
Thanks in advance. --Itu (talk) 23:04, 16 July 2020 (UTC)

I made the image with my own software, using comet trajectory from JPL Horizons. There's no easy way to share the sourcecode since it is many tens of thousands of lines of code. The specific code that just drew the trajectory could be made smaller of course, but its not trivial or an effective use of my time to extract. At some point in the future I might convert to a JavaScript program that would draw in a webpage, and that probably would be subset features like this, but not there yet. I have experimented with WebGL, like [1], but couldn't produce stereographic views like this chart. Tomruen (talk) 07:04, 17 July 2020 (UTC)

Hi.

First: thank you for that great image!

My demand is basically about how files are generated, because of confirmability/traceability/reproducibility in an encyclopedic context.

So, you should just state the source of the used data, and secondly telling the program.

Of course you are not urged to disclose you own/proprietary program. This line is just about file-generating scripts - not about processing software (but you should tell the name of it).

Cheers. --Itu (talk) 07:56, 17 July 2020 (UTC)

The main validation we have are comparisons to other similar maps. My map is wide angle, sterographic projection, but with constellation figures, you can compare to others, like Sky&Telescope shows a partial path for July 2020. Tomruen (talk) 08:30, 19 July 2020 (UTC)

Brightness

Tomruen , i suppose the area of the circels is proportional to luminosity - but how is that calculated? --Itu (talk) 08:20, 19 July 2020 (UTC)

The radius of the circles are proportional to distance, as if it was a constant diameter sphere in space. Brightness is indeed proportional to distance squared, related to area. However brightness is also dependent upon distance from the sun, so they are not accurately proportional to brightness over time. That adjustment could be done by changing the pixel brightness proportional to distance to the sun. Tomruen (talk) 08:25, 19 July 2020 (UTC)