Grant Hutchison's Grids for Celestia Objects

This Celestia Add-on requires Celestia v1.3.1prerelease9 or later.

Unzipped into your Celestia \extras folder, this file creates a directory called \Grids, which contains the two ssc files and three png textures necessary to add latitude/longitude grids to bodies in Celestia's Solar System.

The grid textures appear as two new options in the Alternate Surfaces menu (activated by right-clicking on a planet or moon). When grid textures are available, you will see "Grid Overlay" and "Blank Grid" appearing as options. "Grid Overlay" places a latitude/longitude grid over the default Celestia texture. "Blank Grid" replaces the Celestia texture with a white surface marked out in latitude/longitude lines.

The grids conform to the IAU standard - north pole to the north of the plane of the ecliptic, longitude increasing to the west for direct rotators and to the east for retrograde rotators. Earth and the Moon have their own grids, with both west and east longitude marked. The grids are colour-coded: blue for direct rotators, green for retrograde rotators, orange for the Earth/ Moon grid. They are ruled at 15-degree intervals, and labelled at 30-degree intervals. Grids are available for the giant planets: in the case of Saturn, Uranus and Neptune, they correspond to the IAU-defined prime meridian for System III rotation (the rotation period of the planetary core); for Jupiter, Celestia uses System II rotation to reproduce the position of the Great Red Spot accurately, so the generated grid does not correspond to the IAU-defined rotation.

Unfortunately, overlays don't work with 3ds objects at present, but the attached zip contains textures and ssc's to lay grids on to the spherical solar system bodies as Alternate Surfaces. I hope overlays will be extended to 3ds soon, in which case it'll be easy enough to update the ssc's.

Grant Hutchison, August 2003

Grid Overlay on several planets

• Grant Hutchison's Contributions for Celestia
  • Saturn's Moons for Celestia v1.3.0
  • Celestia's Invisible Object (new for v1.3)
  • Placing objects at defined locations on planetary surfaces
    (Modified for use with Celestia v1.3)
  • Zubrin Statites to Terraform Mars
  • Corrections for Celestia v1.2.5

• Selden's List of Celestia Resources

---

The content of this Web page was provided by Grant Hutchison.

This Web page is maintained by Selden Ball at Wilson Lab.
Please send any comments or corrections to seb@lepp.cornell.edu