OF THE ROGER N. CLARK

VISUAL ASTRONOMY OF THE DEEP SKY
Table C.2. BASIC Program ASTROPOS
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APPENDIX C: AIR MASS, ATMOSPHERIC EXTINCTION
Table C.2 (cont. )
-
1 REM
2 REM
3 REM
4 REM
5 REM
6 REM
7 REM
8 REM
9 REM
10 REM
11 REM
12 REM
13 REM
14 REM
15 REM
16 REM
17 REM
18 REM
19 REM
20 REM
21 REM
22 REM
23 REM
24 REM
25 REM
26 REM
27 REM
28 REM
Definitions :
LONGII= longitude in decimal degree s
LONGRII = long in radians = LONGII*57.29577951
LONGD degree portion of longitude , west= +, east= -
LONGM
LONGS
minutes po rtion of longitude
seconds portion of longitude
LATII = latitude in decimal degrees
LATR# , LATD , LATM , LATS= same as in longitude , but corresponding
to latitude of the observer on the earth
SO# sidereal time at Greenwich at 0 hour s UT on date of observation
STII Sidereal time , decimal days
UTII Universal time in decimal days
HAil hour angle in radians
RAil object Right Ascension in radians
DECII = ob je ct Declination in radians
CZA# = cosine of the zeni th angle , uncorrected for re fraction
ZHII = zenith angle to the horizon
TSET# = set time of an object in decimal days
TRISE# = rise time of an object in decimal days
Zcorrll = zenith angle of an object , corrected for refraction
ZA# = zenith angle of an object , not correc ted for refraction
ALT# = altitude of an object
AZIMII = azimuth of an object (O=north , 90=east , 180=south , 270=west)
AIRMAS = air mass of an object , relative to overhead (where =1 .0)
H = he ight (elevation) of observer in feet
29 REM ----------------------------------------------------------------------
30 REM
31 REM ********** the value of PI:
32 PIU = 3. 1415926536#
33 REM
34 REM ********** the value of one half PI:
35 PIHALF# = PIU /2 !
36 REM
37 REM ********** number of degrees pe r radian :
38 ONERAD# = 57 . 2957795 1#
39 REM
99 REM *** Begin Program ***
100 GOSUB 1500 REM input long lat elevat ion pressure tempc
104 REM setup day
106 INPUT "date of observation in MM ,DD,YYYY" ; MM,DD,YY
107 Y=YY : M=MM: D=DD
108 GOSUB 2100 REM Cal to JD and compSO
109 JJJII = J111
110 REM setup RA
115 GOSUB 1400 REM inp RA DEC
120 REM setup name
25 INPUT name of object" ; OBJNAM$
1 .
130 R EM se
up 1me s
1 35 INPUT
140 INPUT
.
beg1n tim 1n H,M S ; BH $,BM,BS
.. .
end t me 1n H,M S ; EH $
EM ,ES :.
..
145 INPUT time 1ncrement 1n H,M,S ; A$ ,A2 ,A3
150 G05UB 1600 REM DMS to Decimal
155 TINCII = AII /24#
160 A$=BH$: A2=BM : A3=BS
165 GOSUB 1600 REM DMS to decimal
170 BUMII = AII/2411
175 A$=EH$: A2=EM : A3=ES
180 GOSUB 1600 REM DMS to dec imal
185 ETIMII = AII /2411
190 CLS
..
1 93 PRINT ******************* ASTROPOS *********************** ..
195 PRINT "Object : ";OBJNAM$
200 DDEGII= RA# *ONERADII / 1 511: GOSUB 1650
20 1 DEG 1=DEG : MIN1=MIN: SEC1=SEC
202 DDEG II= DEC#*ONERADII : GOSUB 1650
203 DEG2=ABS (DEG): MIN2=MIN: SEC2=SEC
20 5 PRINT USING "Position : RA= ##_h ##_m 11# .1I1I1I_s " ; DEG1 ;MIN1 ;SEC1 ;
206 IF XSIGN=l THEN XCHAR$="+" ELSE XCHAR$="-"
207 PRINT USING " DEC= #11" ;DEG2 ;: PRINT CHR$ (248) ;
208 PRINT USING " ## ' 1I#.#ff";MIN2; SEC2 ;: PRINT .. .. ..
210 PRINT
2 15 PRINT USING "Date : ## /fill /1111## ";MM;DD;YY;
216 PRINT USING JUlian Day at 0 hours l1li11#1111#11. ##" ;JJJII
220 REM
225 PRINT "Observation site:";
230 IF SLONG=l THEN XCHAR$=" .. ELSE XCHAR$="-"
235 PRINT " Longitude : "; XC HAR $ ;
236 PRINT USING "1I1111" ;LONGD; : PRINT CHR$ (248) ;
237 PRINT USING " 1111 ' 1111.11#"; LONGM ; LONGS ;: PRINT CHR$ (34) ;
240 IF SLAT=l THEN XCHAR$=" " ELSE XCHAR$="-"
241 PRINT " Lat itude: ";XCHAR$ ;
242 PRINT USING "111111" ;LATD ;: PRINT CHR$ (248);
243 PRINT USING " 1111 ' 1I#.III1" ;LATM ; LATS ;: PRINT CHR$ (34)
245 PRINT USING " - Elevation: 1111 111111# . feet" ;H;
246 PRINT USING " Pressure: #111111 . mbar ";PRESSURE;
247 PRINT USING " Temperature : 11111111 c" ;TEMPC
250 REM
254 GOSUB 1270 REM ZanglHoriz
255
GOSUB 2300 REM cosineHA (of horizon)
260 GOSUB 2400 REM settime
265 GOSUB 2450 REM rise time
267 REM
270 PRINT USING "zenith angle to hor izon : 11111111.111111 degrees" ;ZHII*ONERADII
27 1 DDAYII = SOli : GOSUB 2030 REM ddaytoHMS
272 PRINT "Sidereal time at Oh UT at Greenwi ch : ";
27 3 PRINT USING "1111 h 1111 m 1111 . 111111 s";HOURS ;MIN; SEC
275 DDAYII = TRISEII :-GOSUB 20 30 REM ddaystoHMS
280 PRINT "Rise time (UT):";HOURS ; "h ";MIN; "m ";SEC ;"s"
28 5 DDAYII = TSETII : GOSUB 2030 REM ddaystoHMS
272
273