10 REM PROGRAM "RISE-SET.BAS," A MBASIC PROGRAM CALCULATING THE LOCAL HOUR ANGLE
20 REM    AND THE LOCAL AZMUTH OF THE RISING OF AN ASTRONOMICAL BODY
30 REM       GIVEN ITS DECLINATION AND THE OBSERVERS LATITUDE
40 REM           REVISED 4-19-1985, MIKE FINERTY, TUCSON
50 REM ***********************************************************************
60 PI = 3.1415926#
70 INPUT "DECLINATION OF BODY IN DEC. DEGREES";D
80 INPUT "LATITUDE OF OBSERVER IN DEGREES.MINS "; LAT
90 DEC = D*PI/180
100 LATITUDE = 100/60*(LAT - INT(LAT))+INT(LAT)
110 L = LATITUDE*PI/180
120 TEST = ABS(DEC)
130 IF TEST > PI/2-ABS(L) THEN 330
140 LHACOS = - TAN(L)*TAN(DEC)
150 AZCOS = SIN(DEC)/COS(L)
160 LHA =PI/2-ATN(LHACOS/(1-LHACOS^2)^.5)
170 AZ = PI/2-ATN(AZCOS/(1-AZC0S^2)^.5)
180 AZ = AZ/PI*180
190 LHA=LHA/PI*12
200 LHA = 24-LHA
210 PRINT "RISING AZMUTH =";AZ;"DEGREES, SETTING AZMUTH =";360-AZ;"DEGREES"
220 PRINT "LHA RISING =";LHA;"HOURS, LHA SETTING =";24-LHA;"HOURS"
230 PRINT "OBJECT VISIBLE FOR";2*(24-LHA);"HOURS."
240 PRINT "ALTITUDE AT UPPER CULMINATION (TRANSIT) =";90-ABS(L-DEC)*180/PI;"DEGREES"
250 IF DEC = L THEN PRINT "CULMINATION AT ZENITH"
260 IF DEC = L THEN GOTO 330
270 IF DEC>L THEN PRINT "TRANSIT NORTH OF ZENITH" ELSE PRINT"TRANSIT SOUTH OF ZENITH"
280 PRINT
290 PRINT "DO YOU WANT ANOTHER OBJECT ? Y/N?"
300 INPUT ANS$
310 IF ANS$ = "Y" GOTO 10
320 END
330 IF SGN(DEC) = SGN(L) THEN PRINT "OBJECT DOES NOT SET"
340 IF SGN(DEC) = -1*SGN(L) THEN PRINT "OBJECT DOES NOT RISE ABOVE HORIZON"
350 GOTO 240