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SLA_EQECL - J2000 $\alpha,\delta$ to Ecliptic

ACTION:
Transformation from J2000.0 equatorial coordinates to ecliptic longitude and latitude.
CALL:
CALL sla_EQECL (DR, DD, DATE, DL, DB)
GIVEN:

DR,DD D J2000.0 mean $[ \alpha,\delta ]$ (radians)
DATE D TDB (formerly ET) as Modified Julian Date (JD$-$2400000.5)
RETURNED:

DL,DB D ecliptic longitude and latitude (mean of date, IAU 1980 theory, radians)


next up previous 269
Next: SLA_EQEQX - Equation of the Equinoxes
Up: SUBPROGRAM SPECIFICATIONS
Previous: SLA_EPV - Earth Position & Velocity (high accuracy)

SLALIB --- Positional Astronomy Library
Starlink User Note 67
P. T. Wallace
19 December 2005
E-mail:ussc@star.rl.ac.uk

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