(35) Locating the Moon - Printable Version +- HP Forums (https://www.hpmuseum.org/forum) +-- Forum: HP Software Libraries (/forum-10.html) +--- Forum: General Software Library (/forum-13.html) +--- Thread: (35) Locating the Moon (/thread-12196.html) |
(35) Locating the Moon - SlideRule - 01-15-2019 01:59 PM An algorithm from the article Using the HP 35 to Locate the Moon, Locating the Moon (Eimac). The following procedure is a technique for using the Hewlett-Packard HP-35 hand held calculator for determining the moon's AZIMUTH in relation to true north, and the ELEVATION with respect to the local horizon for the geographical location in question. BEST! SlideRule RE: (35) Locating the Moon - Thomas Klemm - 02-08-2019 07:18 AM This program is for the HP-42S: Code: 00 { 32-Byte Prgm } Example: 37.33 ENTER 122.13 ENTER 80.85 ENTER 23.36 XEQ "MOON" y: 99.6580 x: 52.0939 It works also for most other HP calculator models that provide polar-rectangular coordinate transformations. Of course it's not restricted to locate the moon but any celestial body. I wasn't aware of moonbounce. Does anyone here has experience with it? Cheers Thomas RE: (35) Locating the Moon - pier4r - 02-08-2019 09:56 AM Quote:I wasn't aware of moonbounce. Listening to the computer history museum podcast (If I am not mistaken), there is the quest of discovering the radar capabilities of the soviets. The problem: you cannot fly an airplane with electronics and detectors deep in the soviet airspace, so it is rather complicated. They started to realize that they can pick up reflected signals from missiles going up and directly from the moon. I suspect the arecibo radar telescope was used for that too. ( https://en.wikipedia.org/wiki/Arecibo_Observatory ) RE: (35) Locating the Moon - PedroLeiva - 02-08-2019 11:31 AM I have modifie this HP-42S program to be use in HP-67, also change the input data procedure to labels A to D for LAT, LONG, GHA and DECL. But I have doubths about the LAT and LOG sings to use. Usually N of equator and E of Greendwich are (+), and (-) for the opposite locations. Is this apply here? Your opinion will be highly appreciated Pedro RE: (35) Locating the Moon - Thomas Klemm - 02-08-2019 05:05 PM (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 } 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 RE: (35) Locating the Moon - PedroLeiva - 02-08-2019 05:51 PM (02-08-2019 05:05 PM)Thomas Klemm Wrote:Same results as yours. Thank you(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? Pedro RE: (35) Locating the Moon - PedroLeiva - 02-09-2019 02:08 AM [/quote] This is a program for HP-67. Some chanches were made: the input information of LAT, LONG, GHA, DECLIN by pressing [A], [B], [C] and [D], the output pressing [E] and [x<>y] Code:
Data A-LATITUDE: 37.33 DEG B-LONGITUDE: -122.13 DEG Convention: N of equator and E of Greenwich are (+), opposite position (-) C-GHA: 80.85 DEG Greenwich Hour Angle (June 2, 1973 at 19:00 GTM) Convention to get Azimuth from true N: 1- If the GHA is east of your longitude A= Azimuth 2- If the GHA is west of your longitude 360 - A= Azimuth D-DECLINATION: +23.36 DEG (June 2, 1973 at 19:00 GTM) Convention: N (+), S (-) Results ELEVATION: 52.0939 DEG AZIMUTH: 99.6580 DEG INSTRUCTIONS Input 37.33 [A] -122.13 [B] 80.85 [C] 23.36 [D] Output [E] x: 52.0939 [x<>y] y: 99.6580 Example2: Data 36 [A] -122 [B] 71 [C] 2 [D] Solution [E] x= 21.9605 DEG [x<>y] y= 113.7316 DEG Example3: Data 36 [A] -122 [B] 181 [C] -2 [D] Solution [E] x= 23.3226 DEG [x<>y] y= -111.1134 DEG [quote] RE: (35) Locating the Moon - Thomas Klemm - 02-09-2019 04:17 AM (02-09-2019 02:08 AM)PedroLeiva Wrote: Some changes were made: the input information of LAT, LONG, GHA, DECLIN by pressing [A], [Β], [C] and [D] We can slightly improve the program E when the input is in registers A - D: Code: 013: 31 25 15 LBL E Cheers Thomas |