Last seen: April 9, 2026 5:20 pm
Simplified horizontal Laplace is astronomic to geodetic correction for any star, any time, any zenith distance.At station Gulf Stream, per the NGS dat...
Pmoran:Having that much solar obs experience, how good are solar azimuths? Bob is using NTP time source via smart phone app. I use the same and compar...
The adjustment of the bubble is important. However, if the bubble is centered in D, and off a bit in R, then 'level' is halfway in between. So, the bu...
And let's have a big round of applause for Bob.He repeated an Astro azimuth on two successive days with only 5" of difference (or there abouts) observ...
And a plumbing pole isn't a good backsite. One set doesn't an azimuth make. 4 sets, 4-6 DRs each, in one session. And average. And software isn't the ...
Last week's azimuth plus today's angle:175-17-10 (az to unknown disc)+ 0-09-04 (measured angle)____________175-26-14 = last week's az to Gulf Stream17...
That's the same az I calc for geodetic
The big advance in GPS in past 8+ years has been in atmospheric modeling. The hazard in geomagnetic disturbances remains.
I have always done it three ways, broadcast and post ephemirides, NASA's AUTOGIPSY. (Fixed integer, multiple receivers, dual freq.). Even at very long...
Even in the late 80s broadcast v. precise ephemeris for phase differential didn't make a lot of difference at the 5 PPM level over 10s of miles. GPS w...
ECEF, for instance. XY is the equatorial plane. Therefore:Longitude = ATAN (Y/X)That's ECEF X and Y.
That's the beauty of it. GPS is geodetic and the difference between Astro geodetic is better known every few years. For instance: the distance mark-to...
TWP and RNG lines are meridians and latitudes. The 25 Standard sections were laid out parallel to the east and west lines of the TWP, by distance. Com...
It goes to the original question: is the C section on a latitudinal curve? And the answer is that per the instructions is no. And the 25 standard sect...
And the meridians and parallels were directed to be used for township and range lines. Not for the interior sections. And in retracing, the instructio...
rfc, post: 365948, member: 8882 wrote: Couldn't say.Here's the other sheet data:*CURRENT SURVEY CONTROLAA8189 ________________________________________...
The instructions are clear. The township is laid first. And center sections are originally set on straight line last connecting the standard corners. ...
There you go. And that dates back to practices from 1851 thru the late 40s."reckoned from south ... as we do now", for no specific reason. And I had f...
That's just the way it was back in the day. Azimuth from south. Maybe due to the tracking stars as they cross the meridian for longitude: due south, A...