HYG 4.1 bright-star subset
Copyright David Nash / Astronexus.
Source: https://github.com/astronexus/HYG-Database/tree/c7f7f883fe678cc7680169a50ccd7dcc49b060ce/hyg/CURRENT
License: Creative Commons Attribution-ShareAlike 4.0 International
https://creativecommons.org/licenses/by-sa/4.0/

Modifications by Kytegyl: only stars of visual magnitude <= 4.5; selected
name, magnitude, color-index, J2000 Cartesian position and velocity fields;
sorted by magnitude; converted CSV to JSON. The derived catalogue remains
available under the same CC BY-SA 4.0 license. No endorsement is implied.

Moon texture: Moon Mosaic, NASA's Scientific Visualization Studio.
Visualizer: Ernie Wright. LRO/NAC photographic mosaic of 1,231 frames.
Source: https://svs.gsfc.nasa.gov/5001/
NASA media guidelines: https://www.nasa.gov/nasa-brand-center/images-and-media/
Downloaded from NASA's official image delivery service at 256 x 256 pixels.
The image file is unchanged; the scene clips its disc and masks the lunar phase.
NASA does not endorse this website or its products.

Astronomy Engine 2.1.19
https://github.com/cosinekitty/astronomy

MIT License
Copyright (c) 2019-2023 Don Cross <cosinekitty@gmail.com>

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