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Lunars: Jupiter's BIG.
From: Frank Reed CT
Date: 2003 Dec 20, 03:53 EST
From: Frank Reed CT
Date: 2003 Dec 20, 03:53 EST
When you shoot lunars with Jupiter, you soon discover that the giant planet has a visible semidiameter through a good sextant. The accepted practice is to split the planet -- you take it to the Moon's limb and place the disk of the planet as best you can with its center right on the limb so that the planet is split in half along the Moon's limb. That's do-able...
Fortunately, Jupiter is far enough away that parallax is no issue (it's always less than 0.04 minutes of arc for Jupiter).
If anyone's interested, here's a set of Jupiter-Moon lunars from last night taken with a reliable Plath sextant:
Index Correction: +0.7
Assumed Position: Lat = 41d 22N, Lon = 71d 57W
Temp: 30F. Pressure: Normal.
All Lunars are Jupiter-Moon-Far Limb. Times are EST (US Eastern Standard Time). Sights start at Greenwich Date 12/19/2003, 09:30:
04:30:37, 43d 49.5
04:33:31, 43d 51.1
04:36:15, 43d 51.7
04:39:15, 43d 53.7
04:43:30, 43d 55.7
04:48:15, 43d 57.6
04:52:30, 44d 00.1
Enjoy!
Frank E. Reed
[X] Mystic, Connecticut
[ ] Chicago, Illinois
Fortunately, Jupiter is far enough away that parallax is no issue (it's always less than 0.04 minutes of arc for Jupiter).
If anyone's interested, here's a set of Jupiter-Moon lunars from last night taken with a reliable Plath sextant:
Index Correction: +0.7
Assumed Position: Lat = 41d 22N, Lon = 71d 57W
Temp: 30F. Pressure: Normal.
All Lunars are Jupiter-Moon-Far Limb. Times are EST (US Eastern Standard Time). Sights start at Greenwich Date 12/19/2003, 09:30:
04:30:37, 43d 49.5
04:33:31, 43d 51.1
04:36:15, 43d 51.7
04:39:15, 43d 53.7
04:43:30, 43d 55.7
04:48:15, 43d 57.6
04:52:30, 44d 00.1
Enjoy!
Frank E. Reed
[X] Mystic, Connecticut
[ ] Chicago, Illinois
