-#!/usr/bin/perl -w
+#/usr/bin/perl -w
#
# This module was written by Steve Franke K9AN.
# November, 1999.
#
# $Id$
#
+# 2005/02/25 add calculation of civil dawn and dusk, defined to be times
+# when solar zenith angle is 96 degrees.
+# 2001/12/16 Fixed Julian_Date_of_Epoch and now I actually use it...
+# 2001/09/15 some changes to take care of cases where the object
+# doesn't rise or set on a given day...
package Sun;
-use POSIX;
require Exporter;
@ISA = qw(Exporter);
use strict;
-use vars qw($VERSION $BRANCH);
-$VERSION = sprintf( "%d.%03d", q$Revision$ =~ /(\d+)\.(\d+)/ );
-$BRANCH = sprintf( "%d.%03d", q$Revision$ =~ /\d+\.\d+\.(\d+)\.(\d+)/ ) || 0;
-$main::build += $VERSION;
-$main::branch += $BRANCH;
-
use vars qw($pi $d2r $r2d);
$pi = 3.141592653589;
use Keps;
use DXVars;
use DXUtil;
+use DXDebug;
+
+use POSIX qw(:math_h);
# reload the keps data
sub load
sub Julian_Date_of_Epoch
{
my $epoch=shift;
- my $year=int($epoch*1e-3);
- $year=$year+2000 if ($year < 57);
- $year=$year+1900 if ($year >= 57);
- my $day=$epoch-$year*1e3;
+ my $year=int($epoch/1000);
+ my $day=$epoch-$year*1000;
+ if ($year < 57 ) {
+ $year=$year+2000;
+ }
+ else {
+ $year=$year+1900;
+ }
my $Julian_Date_of_Epoch=Julian_Date_of_Year($year)+$day;
return $Julian_Date_of_Epoch;
}
+
sub Julian_Date_of_Year
{
my $year=shift;
my $lat = shift;
my $lon = shift;
my $sun0_moon1=shift; # 0 for sun, 1 for moon, 2 for venus...
+ my ($alpha1,$delta1,$alpha2,$delta2,$alpha3,$delta3);
+ my ($aznow,$hnow,$alphanow,$deltanow,$distance,$distancenow);
+ my ($h0,$H);
+ my ($risetime,$settime);
+ my ($dawntime,$dusktime);
- my ($alpha1,$alpha2,$alpha3,$delta1,$delta2,$delta3);
- my ($m0,$m1,$m2,$theta,$alpha,$delta,$H,$az,$h,$h0,$aznow,$hnow,$corr);
- my ($i,$arg,$argtest,$H0,$alphanow,$deltanow,$distance,$distancenow);
+ my ($ifrac,$ifracnow);
my $julianday=Julian_Day($year,$month,$day);
my $tt1 = ($julianday-1-2451545)/36525.;
($alpha2, $delta2)=get_sun_alpha_delta($tt2);
($alpha3, $delta3)=get_sun_alpha_delta($tt3);
($alphanow, $deltanow)=get_sun_alpha_delta($ttnow);
- $h0=-0.8333;
$H=$thetanow-$lon-$alphanow;
$H=reduce_angle_to_360($H);
($aznow,$hnow)=get_az_el($H,$deltanow,$lat);
$hnow=$hnow +
1.02/(tandeg($hnow+10.3/($hnow+5.11)))/60;
+ $h0=-0.8333; # this is for sun rise and sun set
+ ($risetime,$settime)=
+ do_rise_set_calculations($h0,$theta0,$lat,$lon,$alpha1,$delta1,
+ $alpha2,$delta2,$alpha3,$delta3);
+ $h0=-6.0; # this is for civil dawn and dusk
+ ($dawntime,$dusktime)=
+ do_rise_set_calculations($h0,$theta0,$lat,$lon,$alpha1,$delta1,
+ $alpha2,$delta2,$alpha3,$delta3);
+ $dawntime = "------" if( $dawntime eq "NoRise" );
+ $dusktime = "------" if( $dusktime eq "NoSet " );
+
+ return (
+ sprintf("%s", $dawntime), sprintf("%s",$risetime),
+ sprintf("%s", $settime), sprintf("%s",$dusktime),
+ $aznow+180,$hnow
+ );
}
if ( $sun0_moon1 == 1 ) {
- ($alpha1, $delta1, $distance)=get_moon_alpha_delta($tt1);
- ($alpha2, $delta2, $distance)=get_moon_alpha_delta($tt2);
- ($alpha3, $delta3, $distance)=get_moon_alpha_delta($tt3);
- ($alphanow, $deltanow, $distancenow)=get_moon_alpha_delta($ttnow);
- $h0=0.7275*$r2d*asin(6378.14/$distancenow)-34./60.;
+ ($alpha1, $delta1, $distance, $ifrac)=get_moon_alpha_delta($tt1);
+ ($alpha2, $delta2, $distance, $ifrac)=get_moon_alpha_delta($tt2);
+ ($alpha3, $delta3, $distance, $ifrac)=get_moon_alpha_delta($tt3);
+ ($alphanow, $deltanow, $distancenow, $ifracnow)=get_moon_alpha_delta($ttnow);
+ $h0=0.7275*$r2d*asin(6378.14/$distancenow)-34.0/60.;
$H=$thetanow-$lon-$alphanow;
$H=reduce_angle_to_360($H);
($aznow,$hnow)=get_az_el($H,$deltanow,$lat);
$hnow=$hnow-$r2d*asin(sin(6378.14/$distancenow)*cosdeg($hnow))+
1.02/(tandeg($hnow+10.3/($hnow+5.11)))/60;
+ ($risetime,$settime)=
+ do_rise_set_calculations($h0,$theta0,$lat,$lon,$alpha1,$delta1,
+ $alpha2,$delta2,$alpha3,$delta3);
+ return (sprintf("%s", $risetime), sprintf("%s",$settime),
+ $aznow+180,$hnow, -40*log10($distance/385000), $ifracnow );
+
}
- $arg = (sindeg($h0)-sindeg($lat)*sindeg($delta2))/(cosdeg($lat)*cosdeg($delta2));
- $argtest = tandeg($lat)*tandeg($delta2);
+}
- if ( $argtest < -1. ) {
- return sprintf("Doesn't rise.");
- }
- if ( $argtest > 1. ) {
- return sprintf("Doesn't set.");
- }
+sub do_rise_set_calculations
+{
+ my $norise = 0;
+ my $noset = 0;
+ my ($risehr,$risemin,$risetime,$sethr,$setmin,$settime);
+ my ($m0,$m1,$m2,$theta,$alpha,$delta,$H,$az,$h,$corr);
+ my ($i,$arg,$argtest,$H0);
+
+ my $h0=shift;
+ my $theta0=shift;
+ my $lat=shift;
+ my $lon=shift;
+ my $alpha1=shift;
+ my $delta1=shift;
+ my $alpha2=shift;
+ my $delta2=shift;
+ my $alpha3=shift;
+ my $delta3=shift;
+
+ $arg = (sindeg($h0)-sindeg($lat)*sindeg($delta2))/(cosdeg($lat)*cosdeg($delta2));
+ if ( abs($arg) > 1. ) { # either up all day or down all day
+ $norise = 1; # leave it to the user to examine
+ $noset = 1; # the elevation angle (or look outside!)
+ } # to figure out which.
$H0 = acos($arg)*$r2d;
my $aa=$alpha2-$alpha1;
$corr=-$H/360;
$m0=$m0+$corr;
$m0=$m0+1 if( $m0 < 0 );
- $m0=$m0-1 if( $m0 > 1 );
+ $m0=$m0-1 if( $m0 >= 1 );
}
- $m1 = $m0 - $H0/360.;
- $m1=$m1+1 if( $m1 < 0 );
- $m1=$m1-1 if( $m1 > 1 );
- for ($i=1; $i<=2; $i++) {
- $theta = $theta0+360.985647*$m1;
- $alpha=$alpha2+$m1*($aa+$ba+$m1*$ca)/2;
- $delta=$delta2+$m1*($ad+$bd+$m1*$cd)/2;
- $H=$theta-$lon-$alpha;
- $H=reduce_angle_to_360($H);
- ($az,$h)=get_az_el($H,$delta,$lat);
- $corr=($h-$h0)/(360*(cosdeg($delta)*cosdeg($lat)*sindeg($H)));
- $m1=$m1+$corr;
+
+ if( !$norise ){
+ $m1 = $m0 - $H0/360.;
$m1=$m1+1 if( $m1 < 0 );
$m1=$m1-1 if( $m1 > 1 );
+ for ($i=1; $i<=2; $i++) {
+ $theta = $theta0+360.985647*$m1;
+ $alpha=$alpha2+$m1*($aa+$ba+$m1*$ca)/2;
+ $delta=$delta2+$m1*($ad+$bd+$m1*$cd)/2;
+ $H=$theta-$lon-$alpha;
+ $H=reduce_angle_to_360($H);
+ ($az,$h)=get_az_el($H,$delta,$lat);
+ $corr=($h-$h0)/(360*(cosdeg($delta)*cosdeg($lat)*sindeg($H)));
+ $m1=$m1+$corr;
+# $norise=1 if( $m1 < 0 || $m1 > 1);
+ $m1=$m1-1 if( $m1 >= 1);
+ $m1=$m1+1 if( $m1 < 0);
+ }
}
- $m2 = $m0 + $H0/360.;
- $m2=$m2+1 if( $m2 < 0 );
- $m2=$m2-1 if( $m2 > 1 );
- for ($i=1; $i<=2; $i++) {
- $theta = $theta0+360.985647*$m2;
- $alpha=$alpha2+$m2*($aa+$ba+$m2*$ca)/2;
- $delta=$delta2+$m2*($ad+$bd+$m2*$cd)/2;
- $H=$theta-$lon-$alpha;
- $H=reduce_angle_to_360($H);
- ($az,$h)=get_az_el($H,$delta,$lat);
- $corr=($h-$h0)/(360*(cosdeg($delta)*cosdeg($lat)*sindeg($H)));
- $m2 = $m2 + $corr;
- $m2=$m2+1 if( $m2 < 0 );
- $m2=$m2-1 if( $m2 > 1 );
- }
- my ($risehr,$risemin,$sethr,$setmin);
- $risehr=int($m1*24);
- $risemin=($m1*24-int($m1*24))*60+0.5;
- if ( $risemin >= 60 ) {
- $risemin=$risemin-60;
- $risehr=$risehr+1;
- }
- $sethr=int($m2*24);
- $setmin=($m2*24-int($m2*24))*60+0.5;
- if ( $setmin >= 60 ) {
- $setmin=$setmin-60;
- $sethr=$sethr+1;
+ if( !$norise ) {
+ $risehr=int($m1*24);
+ $risemin=($m1*24-int($m1*24))*60+0.5;
+ if ( $risemin >= 60 ) {
+ $risemin=$risemin-60;
+ $risehr=$risehr+1;
+ }
+ $risehr=0 if($risehr==24);
+ $risetime=sprintf("%02d:%02dZ",$risehr,$risemin);
+ } else {
+ $risetime="NoRise";
}
- if ( $sun0_moon1 == 0 ) {
- return (sprintf("%02d:%02dZ", $risehr,$risemin), sprintf("%02d:%02dZ",$sethr,$setmin),$aznow+180,$hnow);
- }
- if ( $sun0_moon1 == 1 ) {
- return (sprintf("%02d:%02dZ", $risehr,$risemin), sprintf("%02d:%02dZ",$sethr,$setmin),
- $aznow+180,$hnow, -40*log10($distance/385000) );
+ if( !$noset ){
+ $m2 = $m0 + $H0/360.;
+ $m2=$m2+1 if( $m2 < 0 );
+ $m2=$m2-1 if( $m2 >= 1 );
+ for ($i=1; $i<=2; $i++) {
+ $theta = $theta0+360.985647*$m2;
+ $alpha=$alpha2+$m2*($aa+$ba+$m2*$ca)/2;
+ $delta=$delta2+$m2*($ad+$bd+$m2*$cd)/2;
+ $H=$theta-$lon-$alpha;
+ $H=reduce_angle_to_360($H);
+ ($az,$h)=get_az_el($H,$delta,$lat);
+ $corr=($h-$h0)/(360*(cosdeg($delta)*cosdeg($lat)*sindeg($H)));
+ $m2 = $m2 + $corr;
+# $noset=1 if( $m2 < 0 || $m2 > 1);
+ $m2=$m2-1 if( $m2 >= 1);
+ $m2=$m2+1 if( $m2 < 0);
+ }
}
+
+ if( !$noset ) {
+ $sethr=int($m2*24);
+ $setmin=($m2*24-int($m2*24))*60+0.5;
+ if ( $setmin >= 60 ) {
+ $setmin=$setmin-60;
+ $sethr=$sethr+1;
+ }
+ $sethr=0 if($sethr==24);
+ $settime=sprintf("%02d:%02dZ",$sethr,$setmin);
+ } else {
+ $settime="NoSet ";
+ }
+ return $risetime,$settime;
}
+
+
+
sub get_moon_alpha_delta
{
#
# Calculate the moon's right ascension and declination
#
+ # As of October 2001, also calculate the illuminated fraction of the
+ # moon's disk... (why not?)
+ #
my $tt=shift;
my $Lp=218.3164477+481267.88123421*$tt-
my $delta=asin(cosdeg($beta)*sindeg($epsilon)*sindeg($lambda)+sindeg($beta)*cosdeg($epsilon))*$r2d;
$delta = reduce_angle_to_360($delta);
- return ($alpha,$delta,$distance);
+# $phase will be the "moon phase angle" from p. 346 of Meeus' book...
+ my $phase=180.0 - $D - 6.289 *sindeg($Mp)
+ + 2.100 *sindeg($M)
+ - 1.274 *sindeg(2.*$D - $Mp)
+ - 0.658 *sindeg(2.*$D)
+ - 0.214 *sindeg(2.*$Mp)
+ - 0.110 *sindeg($D);
+
+# $illum_frac is the fraction of the disk that is illuminated, and will be
+# zero at new moon and 1.0 at full moon.
+
+ my $illum_frac = (1.0 + cosdeg( $phase ))/2.;
+
+ return ($alpha,$delta,$distance,$illum_frac);
}
sub get_sun_alpha_delta
my $epoch = $sat_ref ->{epoch};
#printf("epoch = %10.2f\n",$epoch);
- my $epoch_year=int($epoch/1000);
- my $epoch_day=$epoch-int(1000*$epoch_year);
-#printf("epoch_year = %10.2f\n",$epoch_year);
-#printf("epoch_day = %17.12f\n",$epoch_day);
- my $ep_year=$epoch_year+2000 if ($epoch_year < 57);
- $ep_year=$epoch_year+1900 if ($epoch_year >= 57);
- my $jt_epoch=Julian_Date_of_Year($ep_year);
- $jt_epoch=$jt_epoch+$epoch_day;
+ my $jt_epoch=Julian_Date_of_Epoch($epoch);
#printf("JT for epoch = %17.12f\n",$jt_epoch);
my $tsince=($jtime-$jt_epoch)*24*60;
#printf("tsince (min) = %17.12f\n",$tsince);