date_sun_info
Returns an array with information about sunset/sunrise and twilight begin/end
Description
array date_sun_info(int $timestamp, float $latitude, float $longitude)
Parameters
-
timestamp
-
Unix timestamp.
-
latitude
-
Latitude in degrees.
-
longitude
-
Longitude in degrees.
Return Values
Returns an array whose structure is detailed in the following list:
-
sunrise
-
The timestamp of the sunrise (zenith angle = 90°35').
-
sunset
-
The timestamp of the sunset (zenith angle = 90°35').
-
transit
-
The timestamp when the sun is at its zenith, i.e. has reached its topmost
point.
-
civil_twilight_begin
-
The start of the civil dawn (zenith angle = 96°). It ends at
sunrise.
-
civil_twilight_end
-
The end of the civil dusk (zenith angle = 96°). It starts at
sunset.
-
nautical_twilight_begin
-
The start of the nautical dawn (zenith angle = 102°). It ends at
civil_twilight_begin.
-
nautical_twilight_end
-
The end of the nautical dusk (zenith angle = 102°). It starts at
civil_twilight_end.
-
astronomical_twilight_begin
-
The start of the astronomical dawn (zenith angle = 108°). It ends at
nautical_twilight_begin.
-
astronomical_twilight_end
-
The end of the astronomical dusk (zenith angle = 108°). It starts at
nautical_twilight_end.
The values of the array elements are either UNIX timestamps, false if the
sun is below the respective zenith for the whole day, or true if the sun is
above the respective zenith for the whole day.
Examples
Example #1 A date_sun_info example
<?php
$sun_info = date_sun_info(strtotime("2006-12-12"), 31.7667, 35.2333);
foreach ($sun_info as $key => $val) {
echo "$key: " . date("H:i:s", $val) . "\n";
}
?>
The above example will output:
sunrise: 05:52:11
sunset: 15:41:21
transit: 10:46:46
civil_twilight_begin: 05:24:08
civil_twilight_end: 16:09:24
nautical_twilight_begin: 04:52:25
nautical_twilight_end: 16:41:06
astronomical_twilight_begin: 04:21:32
astronomical_twilight_end: 17:12:00
Example #2 Polar night, with some processing
<?php
$tz = new \DateTimeZone('America/Anchorage');
$si = date_sun_info(strtotime("2022-12-21"), 70.21, -148.51);
foreach ($si as $key => $value) {
echo
match ($value) {
true => 'always',
false => 'never',
default => date_create("@{$value}")->setTimeZone($tz)->format( 'H:i:s T' ),
},
": {$key}",
"\n";
}
?>
The above example will output:
never: sunrise
never: sunset
12:52:18 AKST: transit
10:53:19 AKST: civil_twilight_begin
14:51:17 AKST: civil_twilight_end
09:01:47 AKST: nautical_twilight_begin
16:42:48 AKST: nautical_twilight_end
07:40:47 AKST: astronomical_twilight_begin
18:03:49 AKST: astronomical_twilight_end
Example #3 Midnight sun (Tromsø, Norway)
<?php
$si = date_sun_info(strtotime("2022-06-26"), 69.68, 18.94);
print_r($si);
?>
The above example will output:
Array
(
[sunrise] => 1
[sunset] => 1
[transit] => 1656240426
[civil_twilight_begin] => 1
[civil_twilight_end] => 1
[nautical_twilight_begin] => 1
[nautical_twilight_end] => 1
[astronomical_twilight_begin] => 1
[astronomical_twilight_end] => 1
)
Example #4 Calculating length of day (Kyiv)
<?php
$si = date_sun_info(strtotime('2022-08-26'), 50.45, 30.52);
$diff = $si['sunset'] - $si['sunrise'];
echo "Length of day: ",
floor($diff / 3600), "h ",
floor(($diff % 3600) / 60), "s\n";
?>
The above example will output: