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Comparison photo of Jupiter near moon

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Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
45/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Active
Tech stack
javascript, three.js
Domain
computer-graphics

Research direction

Start by reproducing the Jupiter-and-moon comparison using the linked Celestiary URL and the provided reference images. The issue lists several separate UI and rendering discrepancies, including Jupiter pixelation, missing stars, exposure, and lunar shading, but names no files or tests. First identify the rendering and UI entry points, then agree on one discrepancy to address; done means that specific difference is improved against the reference.

Written by the indexing model from the issue text.

Description

bug

From: https://www.facebook.com/photo/?fbid=10247450985194970&set=gm.28690380737296532&idorvanity=718992471528734

"Early this morning, the Moon passed in front of Jupiter, blocking Jupiter for about an hour. In this image, Jupiter and four of its moons are emerging from behind the Moon. The Moon is sliding away toward the lower left. From any location on Earth, this happens about every 10-20 years. Taken from Bay Village." - Frank Shoemaker Post Oct 7 2026, so presumably the early morning of Oct 6 and Bay Village, Ohio seems to work

Actual:
Image

Celestiary:
https://celestiary.github.io/#sun/[email protected],-82.3901,169m;from=sun/earth;t=9774.891jd;cq=0.3372,-0.7003,-0.112,0.6191;fov=0.91deg;s=oL
Image

The photo may be a bit overexposed, but it's still a pretty useful level.

UI issues:

  1. track should not lock roll. 't' for track is very useful for running time forward and backwards to find the moment, but it also locks the view's roll, so i had to keep turning it off and re-rolling manually
  2. time delta should editable during pause. similar to 1, 'j', 'k' and 'l' are useful to speed up, slow down and reverse time to find the moment, but delta can't be edited during pause, which is often when you want to base from.

rendering issues:

  1. Jupiter is getting pixelated - high priority
  2. no crater roughness along the moon's terminator
  3. missing the couple of stars to the right of Jupiter seen in both, and a few other
  4. missing sky glow, tho debatable how desirable this is.. we could just simulate clear sky conditions by default. curious how much glow should be there on clearest skies tho

and another https://www.facebook.com/photo/?fbid=1701755441306341&set=a.201432234672010:
Actual:
Image

Celestiary
https://celestiary.github.io/web/pr-preview/pr-187/#sun/[email protected],-82.3901,169m;from=sun/earth;t=9774.8935jd;cq=-0.2256,-0.7506,0.3328,0.5244;fov=0.63deg;s=lpoL
Image

UI issues:

  1. Needs overall exposure control to allow boosting to fit target image

Rendering issues:

  1. Missing stars

and another for later calibration needing more stars and better white balance/exposure on the moon
Image

more at different exposures, fov (https://www.facebook.com/photo/?fbid=3132273383644659&set=gm.984224191430128&idorvanity=188931684292720):
Image

Image Image Image

"In Bavaria, it was at 12.25 here":
Image

Dominant language
JavaScript
Stars
55
Forks
4
Avg merge
10h 12m
Merged PRs (30d)
134

Getting set up

This project ships no dev container, Dockerfile or contributing guide, so setting up is up to you: start from its README, and see our first-contribution guide for the general steps.

First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

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