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Latitude and Longitude by Meridian Altitude of One Star
I have been toying around with an idea for the last few days, and this evening I tested it out.
Around astronomic twilight I set up my new style T-2 and lightbox on the back patio. I had previously checked my wristwatch against UT from the USNO and established the correction. I also laid in a small supply of suds.
So I sat down in a reclining patio chair and waited. I know a few of the brighter stars by heart, so when Deneb appeared around 9 pm, I knew I was looking slightly east of north. Venus happened to be passing just west of south, so I used the opportunity to focus the view and crosshairs. As I waited for a few more stars to appear so I could figure constellations, I sipped a cold one and was treated to a nice white meteor appearing in Draco and moving west.
A few minutes after 9pm I could barely see Polaris. I took a quick sight and computed it’s azimuth on the laptop as 24 minutes east. I set that angle in the T-2 and set the vertical hair on Alpha Polaris. I then turned back to zero and dumped over and found to my consternation I was dead on line with my neighbors pine tree. So much for planning.
Well, I could see Antares and knew I had just minutes until it crossed the meridian, so I prayed.
And sure enough as I sighted it, it passed through a gap in the pine needles and I set the horizontal wire upon it. I glanced at my watch and began to count. After a few seconds I turned back to the T-2, still counting and watched as Antares approached and split the vertical wire as I adjusted the horizontal wire. I then checked the altitude and plugged it into the laptop and added the UT time I had counted as Antares crossed the wire.
And, well, I am a full 7 tenths of a degree off in Longitude. But only 2 tenths of a degree off in latitude.
Beer me!
Now, the point of the exercise, is that in order to compute one astronomical coordinate, you need a ballpark value for the other. So, a minor success on the first try.
[img=thumbnail]http://img.photobucket.com/albums/v233/ssz0407/Astro%20Pictures/LATLONG.jpg[/img]
P.S. According to google my latitude is 40.40 and my longitude 74.30.
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