Coordinate transform component; J2000 - apparent - local topocentric

Namespace: ASCOM.Astrometry.Transform
Assembly: ASCOM.Astrometry (in ASCOM.Astrometry.dll) Version: (


public class Transform : ITransform, IDisposable
Visual Basic
Public Class Transform _
	Implements ITransform, IDisposable
Visual C++
public ref class Transform : ITransform, 


Use this component to transform between J2000, apparent and local topocentric (JNow) coordinates or vice versa. To use the component, instantiate it, then use one of SetJ2000 or SetJNow or SetApparent to initialise with known values. Now use the RAJ2000, DECJ200, RAJNow, DECJNow, RAApparent and DECApparent etc. properties to read off the required transformed values.

The component can be reused simply by setting new co-ordinates with a Set command, there is no need to create a new component each time a transform is required.

Transforms are effected through the ASCOM NOVAS.Net engine that encapsulates the USNO NOVAS 3.1 library. The USNO NOVAS reference web page is: and the NOVAS 3.1 user guide is included in the ASCOM Developer Components install.

Inheritance Hierarchy


See Also