Sadeem Open Data

Sadeem's reference table, used to add your own objects to the app, is built from two open catalogues published under the Creative Commons Attribution-ShareAlike 4.0 International licence (CC BY-SA 4.0):

• OpenNGC by Mattia Verga — https://github.com/mattiaverga/OpenNGC
• HYG Stellar Database 4.4 by David Nash (astronexus) — https://codeberg.org/astronexus/hyg

Our adapted table is available here under the same licence, CC BY-SA 4.0. You may share and adapt it, including commercially, as long as you credit the original authors and Sadeem, and share your adaptations under the same licence.

Files

• reference-objects.json — the adapted table (CC BY-SA 4.0)
• LICENSE-CC-BY-SA-4.0.txt — the full licence
• reference_tables.py — the script that builds the table, published so the changes can be seen (MIT licence)

What we changed

The table converts both catalogues into one compact file and trims them:

• stars come from HYG: every star brighter than magnitude 6.5 and every star with a proper name;
• deep-sky objects come from OpenNGC; its star, asterism, association, duplicate, group, non-existent and nova entries are left out, and duplicates become aliases of the object they repeat;
• coordinates are converted to decimal degrees, and each row records which of Sadeem's own objects it is, if any.

Attribution: "Contains data from OpenNGC by Mattia Verga and the HYG Stellar Database by David Nash, adapted by Sadeem, CC BY-SA 4.0."

This licence applies only to the files on this page. The rest of Sadeem — its software, text, lessons, illustrations and design — is not covered by it; see the Terms of Use.