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Re: Nautical almanac 1773
From: Dave Walden
Date: 2007 May 01, 19:57 -0700
From: Dave Walden
Date: 2007 May 01, 19:57 -0700
Below are output from the xephem program. First for GAT. The first ANTARES is the one I previously cited, 48-18-20. It turns out the data base I had told xephem to use did not correctly handle proper motion. Using the 2002 version of the SKY2000 data base, the second Antares, I get 48-18-16 for the GAT result, as does Frank. For GMT, where I previously quoted, 48-14-59, I now reproduce Frank's 48-14-56. Cns RA HA GHA Dec Az Sep Sun Cnc 8:47:22.82 24:00:00.00 24:00:00.00 17:55:15.4 180:00:00 163:57:17 Moon Sgr 19:40:21.51 13:07:01.30 13:07:01.30 -16:38:13.8 27:05:51 0:00:00 ANTARES Sco 16:15:34.12 16:31:48.70 16:31:48.70 -25:54:35.9 90:32:04 48:18:20 Antares Sco 16:15:34.38 16:31:48.44 16:31:48.44 -25:54:30.9 90:31:56 48:18:16 Equ: Geo EOD 8/01/1773 13:05:50 BST Site: Greenwich, England Lat: 51:30:00 Long: 0:00:00 Elev: 74.7m Temp: 10C Pres: 1010mB Cns RA HA GHA Dec Az Sep Sun Cnc 8:47:21.88 23:54:10.05 23:54:10.05 17:55:19.1 177:29:32 163:54:12 Moon Sgr 19:40:07.38 13:01:24.55 13:01:24.55 -16:38:42.0 24:58:00 0:00:00 ANTARES Sco 16:15:34.12 16:25:57.81 16:25:57.81 -25:54:35.9 89:23:23 48:14:59 Antares Sco 16:15:34.38 16:25:57.55 16:25:57.55 -25:54:30.9 89:23:16 48:14:56 Equ: Geo EOD 8/01/1773 13:00:00 BST Site: Greenwich, England Lat: 51:30:00 Long: 0:00:00 Elev: 74.7m Temp: 10C Pres: 1010mB Just to check things, I tried 17 May 1781 3hrs (NA says 62-2-49). GMT GAT Frank 62-3-48 62-2-18 xephem 62-3-51 62-2-20 Lunars Almanac for May 17, 1781 Date and Times are GAT. 0:00 3:00 6:00 9:00 12:00 15:00 18:00 21:00 Moon's HP 54.28 54.26 54.23 54.21 54.18 54.17 54.16 54.15 Geocentric Lunar Distances α Aquilae 56° 28' 46" 57° 34' 20" 58° 40' 30" 59° 47' 15" 60° 54' 32" 62° 2' 18" 63° 10' 33" 64° 19' 15" -FER, Centennia Software, June 2004. Lunars Almanac for May 17, 1781 Date and Times are GMT. 0:00 3:00 6:00 9:00 12:00 15:00 18:00 21:00 Moon's HP 54.28 54.26 54.23 54.21 54.18 54.17 54.16 54.15 Geocentric Lunar Distances α Aquilae 56° 30' 13" 57° 35' 48" 58° 41' 59" 59° 48' 44" 60° 56' 2" 62° 3' 48" 63° 12' 4" 64° 20' 46" -FER, Centennia Software, June 2004. Cns RA HA GHA Dec Az Sep Sun Tau 3:38:38.30 3:03:58.96 3:03:58.96 19:30:10.4 245:48:12 63:11:43 Moon Aqr 23:42:44.62 6:59:52.63 6:59:52.63 -5:36:06.1 278:18:44 0:00:00 Altair Aql 19:40:06.75 11:02:30.51 11:02:30.51 8:18:01.0 343:42:03 62:03:51 Equ: Geo EOD 5/17/1781 16:00:00 BST Site: Greenwich, England Lat: 51:30:00 Long: 0:00:00 Elev: 74.7m Temp: 10C Pres: 1010mB Cns RA HA GHA Dec Az Sep Sun Tau 3:38:37.64 3:00:00.00 3:00:00.00 19:30:08.1 244:47:18 63:13:31 Moon Aqr 23:42:37.63 6:56:00.01 6:56:00.01 -5:37:00.4 277:31:27 0:00:00 Altair Aql 19:40:06.75 10:58:30.89 10:58:30.89 8:18:01.0 342:35:31 62:02:20 Equ: Geo EOD 5/17/1781 15:56:01 BST Site: Greenwich, England Now I see a 2-3 sec difference again. Altair has a relavitely high proper motion, using different catalogs, I can get down to 62-2-19, but not quite to 18. Can Frank provide his Moon RA and Dec to .01 sec and his RA, Dec, PM's for Altair so I can check into the source of the difference? Altair0,f|D|A7,19:50:47.00|543.3,8:52:5.96|385.6,0.93,2000 Altair1,f|D|A7,19:50:47.00|538.0,8:52:6.00|386.6,0.93,2000 Altair2,f|D|A7,19:50:47.002|544.5,8:52:6.03|386.0,0.93,2000 Altair3,f|D|A7,19:50:47.001|543.0,8:52:6.07|387.0,0.93,2000 Altair4,f|D|A7,19:50:46.999|536.82,8:52:5.96|385.54,0.93,2000 Altair5,f|D|A7,19:50:46.999|537.60,8:52:5.98|388.00,0.93,2000 Cns RA HA GHA Dec Az Sep Sun Tau 3:38:37.64 3:00:00.00 3:00:00.00 19:30:08.1 244:47:18 63:13:31 Moon Aqr 23:42:37.63 6:56:00.01 6:56:00.01 -5:37:00.4 277:31:27 0:00:00 Altair0 Aql 19:40:06.75 10:58:30.89 10:58:30.89 8:18:01.0 342:35:31 62:02:20 Altair1 Aql 19:40:06.82 10:58:30.81 10:58:30.81 8:18:00.8 342:35:30 62:02:19 Altair2 Aql 19:40:06.73 10:58:30.91 10:58:30.91 8:18:01.0 342:35:31 62:02:21 Altair3 Aql 19:40:06.75 10:58:30.89 10:58:30.89 8:18:00.8 342:35:31 62:02:20 Altair4 Aql 19:40:06.84 10:58:30.80 10:58:30.80 8:18:01.0 342:35:29 62:02:19 Altair5 Aql 19:40:06.82 10:58:30.81 10:58:30.81 8:18:00.5 342:35:29 62:02:19 Equ: Geo EOD 5/17/1781 15:56:01 BST Site: Greenwich, England Lat: 51:30:00 Long: 0:00:00 Elev: 74.7m Temp: 10C Pres: 1010mB --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to NavList@fer3.com To , send email to NavList-@fer3.com -~----------~----~----~----~------~----~------~--~---