NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Lunar attempt
From: Doug Royer
Date: 2003 May 7, 11:04 -0700
From: Doug Royer
Date: 2003 May 7, 11:04 -0700
I would like some help from you guys to check some precomputations for a Lunar attempt this weekend if practical.My software can only perform intercepts and LOP positioning so it isn't any help on this.It doesn't have a starfinder feature.I've used Ho-2102D to precompute this info and just need to know if I'm in the ballpark. I've weaseled my way onboard an 85 ft. SAR vessel to be positioned off San Nicolas Island, position approximately 34* 04' N 120* 22.5' W, 05-10 thru 05-12.This will give me a stable platform to attempt this as it will be anchored on the lee side of the island.The actual position will only be known once the pick is set but this is a good AP. It appears that Regulus is the only star in the appropriate position with the Moon to attempt this.Am I right or wrong? If conditions are right to do this I've precompted times for both nights 05-10 and 05-11.I should be able to see the horizon at these times clear enough to take the altitudes. Useing Ho-2102D I am only able to get a rough idea of the bodies alts., Zn and angular distance. It appears on 05-10 the Moon and Regulus are seperated by less distance than during 05-11.I'll be attempting this both nights but seem to recall someone writeing that the greater the distance of the bodies the better.Am I reading this correctly?Their altitudes are fairly equal during these times.Because of the area I estimate the vessel will be positioned I will only be able to view Regulus untill 2300 hrs. zt.All times are zt, gmt = + 7 hrs. 05-10. 2000 hrs. Reg. alt. = 68* Moon alt. = 66* angular distance = 30* 2100 hrs. Reg. alt = 63* Moon alt. = 68* " " = 27* 2200 hrs. Reg. alt. = 54* Moon alt. = 62* " " = 20* 2300 hrs. Reg. alt = 43* Moon alt. = 53* " " = 15* 05-11 2000 hrs. Reg. alt. = 68* Moon alt. = 55* " " = 48* 2100 hrs. Reg. alt. = 63* Moon alt. = 61* " " = 57* 2200 hrs. Reg. alt. = 54* Moon alt. = 61* " " = 48* 2300 hrs. Reg. alt. = 42* Moon alt. = 56* " " = 36* I didn't include the LHA aries etc. even though they were calculated to use the 2102.If needed write back and I will provide.If you see another body to use before 2300 hrs. zt let me know and I will precompute.In case the conditions are such as I can't use Regulus I want to be prepared. Thanks