astro_helio_vector

Calculates the position of a celestial body as a vector using the center of the Sun
as the origin. The result is expressed as a Cartesian vector in the J2000 equatorial system
(the mean equator of the Earth at noon UTC on 1 January 2000).

Provides access to the 'Astronomy Engine' C library
(<https://github.com/cosinekitty/astronomy>) by Don Cross. The library
calculates positions of the Sun, Moon, and planets, and predicts
astronomical events such as rise/set times, lunar phases, equinoxes,
solstices, eclipses, and transits. It is based on the 'VSOP87' planetary
model and is accurate to within approximately one arcminute. This package
bundles the single-file C source so that other R packages can link against
it via 'LinkingTo' without shipping their own copy.

Mitchell O'Hara-Wild

astronomyengine

R Bindings to the 'Astronomy Engine' C Library

Don Cross

astro_helio_vector function

<dl><dt>body</dt>
<dd>Identifier of celestial body (e.g., <code>astro_body[["SUN"]]</code>, <code>astro_body[["MARS"]]</code>).</dd>
<dt>time</dt>
<dd>A POSIXct time value.</dd></dl>

Arguments

Heliocentric position vector of a celestial body — astro_helio_vector

<dl>

<dt>body</dt>
<dd>Identifier of celestial body (e.g., <code>astro_body[["SUN"]]</code>, <code>astro_body[["MARS"]]</code>).</dd>


<dt>time</dt>
<dd>A POSIXct time value.</dd>

</dl>

astro_helio_vector: Heliocentric position vector of a celestial body

Description

Usage

Value

Arguments

Details

Examples