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When to use Celestial Coordinate Systems 3D Explorer

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Use this explorer when you need to see how a published RA/Dec position relates to what is actually above your horizon - and skip it when you only want star patterns or the Sun path.

  • Classroom demos of why stars rise and set while their RA/Dec stay fixed
  • Showing how the celestial pole altitude equals the observer latitude
  • Introducing the 23.44 degree obliquity of the ecliptic

This is an educational grid visualization at the J2000 epoch, not a live star catalog or planetarium.


Celestial coordinate key figures

Celestial coordinate key figures in one view: Coordinate Systems Sky shows right ascension 0h-24h, declination -90 to +90 deg, plus altitude and azimuth ranges for horizon work.

Compare the celestial coordinate key figures: right ascension, declination, altitude, and azimuth.
Celestial coordinates: RA, declination, altitude, and azimuth ranges.
CoordinateRange
Right Ascension (RA)0h-24h eastward (1h = 15 deg)
Declination (Dec)-90 to +90 deg
Altitude (Alt)0-90 deg
Azimuth (Az)0-360 deg from North
Ecliptic obliquity23.44 deg (J2000)

Walk the controls in the step-by-step guide, or compare options in vs alternatives. Open the Celestial Coordinate Systems 3D Explorer.

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