Astro:...NutEqu(3pm)

💫 Astro::Montenbruck::NutEqu — bestie edition 💫

okay so this is the Astro::Montenbruck::NutEqu page from the User Contributed Perl Documentation, and it's literally all about the obliquity of the ecliptic & nutation. tiny module, big main character energy. let's get into it 🎀

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✨ NAME ✨

Astro::Montenbruck::NutEqu — Obliquity of the ecliptic & nutation. that's it, that's the whole vibe 🦋

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🌸 SYNOPSIS 🌸

so say you've got these mean geocentric coordinates $x0, $y0, $z0 and you wanna glow them up into apparent coordinates $x1, $y1, $z1. here's the move:

# given mean geocentric coordinates $x0, $y0, $z0,
# transform them to apparent coordinates $x1, $y1, $z1
my $func = nutequ( $t );
($x1, $y1, $z1) = $func->($x0, $y0, $z0); # true coordinates

see how nutequ( $t ) hands you back a function and then you call it on your coords? that's the little two-step. slay 💅

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💜 DESCRIPTION 💜

Functions dealing with ecliptic obliquity. that's the whole description fr fr — it's a short queen and she knows it 👑

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🧚 SUBROUTINES 🧚

⭐ deltas( $t )

Calculates the effects of nutation on the ecliptic longitude and on the obliquity of the ecliptic, with accuracy of about 1 arcsecond. you give it time in Julian centuries since J2000 and it hands you back delta-psi and delta-eps. no cap, that's genuinely all it does 😌

Arguments

• $t — time in Julian centuries since J2000: "(JD-2451545.0)/36525.0"

Returns

"($delta_psi, $delta_eps)", in arc-degrees.

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🦋 mean2true($t)

Returns function for transforming of mean to true coordinates. yes bestie, it returns a function — higher-order goodness, we love to see it 🫶

Arguments

• $t — time in Julian centuries since J2000: "(JD-2451545.0)/36525.0"

Returns

Function which takes mean ecliptic geocentric rectangular coordinates "X, Y, Z" of a planet and returns ecliptic rectangular coordinates, referred to the equinox of date.

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🌈 obliquity( $t )

Given time in Julian centuries since J2000, return mean obliquity of the ecliptic, in arc-degrees. one arg in, one number out, iconic behaviour honestly ✨

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👑 AUTHOR 👑

Sergey Krushinsky, "<krushi at cpan.org>" — legend 💖

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🎀 COPYRIGHT AND LICENSE 🎀

Copyright (C) 2009-2022 by Sergey Krushinsky

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

fr fr, same terms as Perl itself — read the Perl license if you wanna get into the legal lore 📜

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okay that's the whole page, you're officially a NutEqu expert now 🎓💅

this was perl v5.42.2, dated 2026-02-15 — mwah, catch you on the next manpage bestie 🍓💜