# DAWN night-sky data attributions

## Constellation figures

The constellation line paths are adapted from
[MarcvdSluys/ConstellationLines](https://github.com/MarcvdSluys/ConstellationLines),
Copyright © 2005–2023 Marc van der Sluys. The source identifies figure vertices
with Bright Star Catalogue (BSC5P) numbers and is licensed under the
[Creative Commons Attribution 4.0 International license](https://creativecommons.org/licenses/by/4.0/).
The citable archive is [DOI 10.5281/zenodo.10397192](https://doi.org/10.5281/zenodo.10397192).

DAWN merges continuation rows into separate paths for the same constellation,
merges the two Serpens source rows into one official constellation entry, and
serializes the BSC identifiers for offline rendering.

## Constellation names and label positions

Official constellation names and edited J2000 label positions are derived from
[d3-celestial](https://github.com/ofrohn/d3-celestial), created by Olaf Frohn and
released under the BSD 3-Clause license. Its data documentation attributes the
names to the International Astronomical Union constellation list and notes that
label positions were edited for display.

DAWN normalizes label longitude to right ascension in the range 0–24 hours,
normalizes `Corona Australis` and the single official `Serpens` name, and adds
flags for the conventional twelve zodiac constellations plus Ophiuchus as an
additional constellation crossed by the ecliptic.

## Stars and ephemerides

Star positions, magnitudes, names, and Harvard Revised identifiers come from
NASA/GSFC HEASARC's Bright Star Catalog (BSC5P), based on Hoffleit and Warren's
5th Revised Edition. Live topocentric positions, visibility, phase, distance,
and rise/set calculations are produced locally with Astronomy Engine.

## Magnified Solar System imagery

The close-up views are historical mission imagery and mosaics, not live
telescope feeds or naked-eye scale. Moon imagery is the NASA Scientific
Visualization Studio LRO/LROC color texture. Planet views use NASA/JPL imagery:
MESSENGER (Mercury), Magellan radar-derived imagery (Venus), Viking (Mars),
Cassini (Jupiter and Saturn), and Voyager 2 (Uranus and Neptune). NASA source
links and a plain-language image label are shown in each object's detail card.

## Planet sphere textures
Equirectangular planet textures (tex-*.jpg, tex-saturn-ring.png) by
[Solar System Scope](https://www.solarsystemscope.com/textures/), licensed
[CC BY 4.0](https://creativecommons.org/licenses/by/4.0/), retrieved via Wikimedia Commons.