planet {moonsun}R Documentation

Compute coordinates of a planet in solar system.

Description

This function computes equatorial coordinates for inner or outer planet for given Julian Day Number.

Usage

planet(jday = jd(), name = "", inner = FALSE, tp, ep, oo, e, a, i, om, th, mag)

Arguments

jday Julian Day Number, default today
name name of a planet (appended to dates in result)
inner TRUE if it is inner, FALSE if outer planet
tp period of a planet (tropical years)
ep longitude at epoch 1990 January 0.00 (degrees)
oo longitude of the perihelion (degrees)
e eccentricity of the orbit
a semi-major axis of the orbit (AU)
i inclination of the orbit (degrees)
om longitude of the ascending node (degrees)
th angular diameter at 1 AU (arcsecs)
mag visual magnitude at 1 AU

Details

The algorithm used here is fairly simple, it does not consider the Kepler equation, nor gravitational influences from other planets. See sun() for details.

This function is not called by user unless calculating a position for planetoid or modified data. The planets() function calls it with appropriate parameters automatically.

Value

An object of class eqc, containing position and other data for requested days, see planets() for details.

Author(s)

Lukasz Komsta

Examples

planets()

[Package moonsun version 0.1 Index]