(35) Locating the Moon

[Thomas Klemm]

(02-08-2019 11:31 AM)PedroLeiva Wrote:  But I have doubts about the LAT and LOG sings to use. Usually N of equator and E of Greenwich are (+), and (-) for the opposite locations. Is this apply here?

Yes. But I had to look up the definitions of GHA and azimuth:

The hour angle may be expressed as negative east of the meridian plane and positive west of the meridian plane.

Azimuth is defined as a horizontal angle measured clockwise from a north base line or meridian.

From looking at the 2 examples on page 6 I assume that the longitude of my example is meant to be in the west as well. Thus we should rather use -122.13.
And since the azimuth is measured clockwise we have to change a sign as well.

This leads to this corrected program:

Code:

00 { 33-Byte Prgm }
01▸LBL "MOON"
02 R↓
03 +
04 X<>Y
05 R↑
06 1
07 →REC
08 R↑
09 X<>Y
10 →REC
11 X<>Y
12 +/-
13 R↓
14 →POL
15 R↓
16 X<>Y
17 -
18 R↑
19 →REC
20 R↓
21 →POL
22 R↑
23 X<>Y
24 →POL
25 R↓
26 END

Line 03 was changed and line 12 was inserted.

Examples:

37.33 ENTER
-122.13 ENTER
80.85 ENTER
23.36 XEQ "MOON"

y: 99.6580
x: 52.0939

---

36 ENTER
-122 ENTER
71 ENTER
2 XEQ "MOON"

y: 113.7316
x: 31.9605

---

36 ENTER
-122 ENTER
181 ENTER
-2 XEQ "MOON"

y: -111.1134
x: 23.3226

I hope that's correct now.

Cheers
Thomas