The GNU 3DLDF Astronomy Page

Celestial Sphere Models

New Model

New Model (July 2026)

2026年07月26日.
This version is completely new. Please Note: It is a work in progress. The model now uses double tabs for the developments. The developments are flat pieces that, when connected to each other, form an approximation to a sphere. In this model, the sphere is divided into 24 spherical biangles, which are, in turn, divided into 288 15° by 15 ° sectors. That is, a spherical biangle comprises 12 sectors.

The data for the stars is now retrieved from the MySQL database, which may optionally be used with GNU 3DLDF. For the astronomy features, however, it is now required.

My goal is to plot at least one star on each sector, including at least the 200 brightest stars. However, since there are 288 sectors and some sectors don't contain any bright stars, while others contain more than one, it will be necessary to plot approximately 300 stars.

The trace of the ecliptic is also plotted on the developments. It would also be possible to plot the traces of the horizons of a selection of locations on the model.

The files listed below are included in the GNU 3DLDF package and the best way to obtain them is to download the latter, install it and run 3DLDF, MetaPost and TeX to generate the generated files oneself. The PDF files are made available here so that everyone may see them, not just users of the package. The other files are included here as a convenience.

See Sources for information on downloading the package from the Git repository.

2026年08月13日.
The files developments_save.pdf and developments_small_save.pdf contain all of the completed pages for sections of the model that have been completed. The files developments.pdf and developments_small.pdf contain the parts needed for the section I am currently working on at any given time. A section will normally be a spherical biangle or a horizontal band. When that section is completed, the pages will be added to the save versions of the files.

PLEASE NOTE: It may be necessary to refresh the page after downloading a file. If a version of the file is in the cache of a user's browser, it otherwise may not be downloaded, even if it is out-of-date.