DSC Parameters recognized by Celestia v1.4.1 (and later)

Contents

0: Introduction.
1.0 DSC Parameters.
2.0 Example.


A.0: Appendices.


A.1: Signature.
A.2: Admonishment.
A.3: Disclaimer.


---

See also:
• Selden's List of Resources for Celestia

0.0 Introduction.

This is a brief description of the parameters recognized by Celestia v1.4.1 in DSC files (Deep Space Catalogs). DSC Galaxy functionality has undergone a substantial improvement when compared to the previous versions of Celestia.

1.0 DSC Parameters.

A DSC catalog file can be used to describe three classes of objects: OpenClusters, Nebulae or Galaxies.

A DSC object definition consists of its class, a quoted name, and its parameters enclosed in braces:

Class "name" { ...parameters... }

• OpenCluster "name"

  "name" is the name of the object. Multiple names can be speciied within the quotes if they're separated by colons (:).

  Currently used only to associate the specified "name" with a position in space.

  • location
    • Position 3 vector
      The position vector's [x y z ] coordinates are in Light Years, specifying a position in Celestia's Ecliptic J2000 "Universal" coordinate system
    or
    • Distance number (default: 1.0) in LightYears
    • RA number (default: 0.0) in fractional Hours (unlike STC catalogs, which use fractional degrees)
    • Dec number (default: 0.0) in fractional degrees

  • orientation (optional)
    • Axis 3 vector (default: [ 1.0 0.0 0.0] )
      a unit vector specifying the orientation of the object's axis in Celestia's Ecliptic J2000 "Universal" coordinate system
    • Angle number (default: 0.0 degrees)
      the amount the object is rotated around that Axis.

  • size
    • Radius number (default: 0.0) in Light Years.

  • information (optional)
    • InfoUrl "string"
      "string" should be the URL of a web page describing the object.

• Nebula "name"

  Places a glowing model at the specified position and orientation
  Uses all of the parameters used for OpenCluster plus

  • Mesh string (optional)
    "string" must be the name of a 3D model file which determines the Nebula's shape. The mesh may require an associated PNG, JPG or DDS surface texture image file to define the Nebula's coloration. If Mesh is omitted, no object is drawn.

• Galaxy "name"

  Places a glowing image of a galaxy at the specified position and orientation
  Uses all of the parameters used for OpenCluster plus

  • Type "string"
    "string" should be one of: S0,Sa,Sb,Sc,SBa,SBb,SBc,E0,E1,E2,E3,E4,E5,E6,E7,Irr

    The Type is shown in Celestia's on-screen informational display. It also determines which PNG image in Celestia's Models directory is used to define the shape of the Galaxy's image.

  • CustomTemplate "string" (optional)
    "string" must be a the name of a PNG image defining the shape of this Galaxy.

  • AppMag or AbsMag

2.0 Example.

Nebula "M16" {
	Mesh "1995-44-a.3ds"
	Axis    [0.205007 -0.737927 -0.642989]
	Angle 146.298

	RA 18.31404
	Dec -13.8311
	Distance 7002
	Radius 3.45
	InfoURL "http://hubble.stsci.edu/newscenter/archive/1995/44/image/a"
}

Contents

0: Introduction.
1.0 DSC Parameters.
2.0 Example.


Appendices.


A.1: Signature.
A.2: Admonishment.
A.3: Disclaimer.


---

See also:
• Selden's List of Resources for Celestia

A.0 Appendices.

A.1: Signature.

This Web page is maintained by Selden Ball at Wilson Lab.

A.2: Admonishment.

Please send any questions, comments or corrections to seb@lepp.cornell.edu
Alternatively, you can post a message (anonymously or otherwise) on Celestia's Web Forum or use its Private Message page.

If you don't tell me that something's missing, unclear or wrong, I can't improve it.

A.3: Disclaimer.

The author disclaims all liability and endorsement.
Copyrights may apply.
For details, please read the full text of his disclaimer.