NAME

Time::Keeper::Star::Day - a star's rises, sets and transits on one civil day at a place

VERSION

Version 0.01

SYNOPSIS

my $sky = Time::Keeper::Sky->new(place => 'Europe/London');
my $d = Time::Keeper::Star->on($date, 'Sirius', place => $sky);
my $d = $sky->on($date, 'Sirius');          # the same

$d->rise;  $d->set;  $d->transit;          # values, or undef
$d->body;                                 # 'Sirius'
$d->hr;                                   # 2491
$d->is_up_all_day;                        # Polaris from London

DESCRIPTION

The day is the place's civil day, as "THE DAY" in Time::Keeper::Sun describes it. A star rises and sets when its centre, seen from the place, is 34 arcminutes below the horizon, as for a planet (Time::Keeper::Planet::Day). A star keeps sidereal time: its events come 3 minutes 56 seconds earlier each day, and a civil day can hold two transits. A star whose distance from the pole is less than the place's latitude never sets (is_up_all_day); one as far from the other pole never rises (is_down_all_day).

METHODS

A Time::Keeper::Star::Day is a Time::Keeper::Body::Day, whose methods it has: rise, set, transit, rises, sets, transits, events, is_up_all_day, is_down_all_day, body, date, zone_name, start, end and place. And:

hr

The star's number in the Bright Star Catalogue.

SEE ALSO

Time::Keeper::Star, Time::Keeper::Body::Day, Time::Keeper::Sky.

AUTHOR

LNATION, <email at lnation.org>

LICENSE AND COPYRIGHT

This software is Copyright (c) 2026 by LNATION.

This is free software, licensed under:

The Artistic License 2.0 (GPL Compatible)