SofaS00a Method

Calculates the CIO locator s, given the IAU 2000A precession-nutation model and the specified Terrestrial Time (TT) date.

Definition

Namespace: ASCOM.Tools
Assembly: ASCOM.AstrometryTools (in ASCOM.AstrometryTools.dll) Version: 3.0.0-rc.1+86c25ce733aebb4d8b1b8a62e84770ea5e972bea

C#

public static double S00a(
	double date1,
	double date2
)

VB

Public Shared Function S00a ( 
	date1 As Double,
	date2 As Double
) As Double

Parameters

date1 Double: The first part of the Terrestrial Time (TT) Julian Date. This value, when combined with date2, specifies the TT date for which to compute the CIO locator.
date2 Double: The second part of the Terrestrial Time (TT) Julian Date. This value, when combined with date1, specifies the TT date for which to compute the CIO locator.

Return Value

Double
The CIO locator s, in radians, for the specified TT date.

Remarks

This function implements the IAU 2000A precession-nutation model as defined by the International Astronomical Union. The date should be supplied as a two-part Julian Date to preserve precision, typically with date1 containing the larger value (e.g., the Julian Day Number) and date2 the fractional day. The CIO locator s is used in high-precision Earth orientation and celestial mechanics calculations.

Version Information

.NET Standard

Supported in: 2.0