Convert from ecliptical to equatorial coordinates, using equations 8.3 and 8.4 of reference 1, or, equivalently, equations 12.3 and 12.4 of reference 2.
eclipticalToEquatorial(lambda, beta, epsilon)A data frame containing columns rightAscension and
declination both in degrees.
longitude, in degrees, or a data frame containing
lambda, beta, and epsilon, in which case the next to
arguments are ignored
geocentric latitude, in degrees
obliquity of the ecliptic, in degrees
Dan Kelley, based on formulae in references 1 and 2.
The code is based on reference 1; see moonAngle() for comments on
the differences in formulae found in reference 2. Indeed,
reference 2 is only cited
here in case readers want to check the ideas of the formulae; DK
has found that reference 2 is available to him via his university library
inter-library loan system, whereas he owns a copy of reference 1.
Meeus, Jean. Astronomical Formulas for Calculators. Second Edition. Richmond, Virginia, USA: Willmann-Bell, 1982.
Meeus, Jean. Astronomical Algorithms. Second Edition. Richmond, Virginia, USA: Willmann-Bell, 1991.
Other things related to astronomy:
angle2hms(),
equatorialToLocalHorizontal(),
julianCenturyAnomaly(),
julianDay(),
moonAngle(),
siderealTime(),
sunAngle(),
sunDeclinationRightAscension()