Until April 1993, the US National Geodetic Survey in its most precise work used a technique known as "orbit relaxation" to account for the relative in...

rfc, post: 366361, member: 8882 wrote: The "Ah Ha!" moment has arrived (Thank you Larry).So far, I've put aside getting too deep into GPS because I do...

JPH, post: 366066, member: 6636 wrote: Anyone have insight into how good of an engineering program U Idaho has?See This link assumes you are intereste...

FWIW, Here is the INVERS3D output verifying Bill93's results: Attached files AA8188_8189.pdf (83.6 KB) 

On the matter of guidance for surveyors interested in astronomy, there are a number of good books on the subject. Many are hard to find or out-of-prin...

Darn, the answer to my question about the rationale for using South azimuth was too easy to find. See: This is a 1945 letter from Senior Mathematici...

Scott Zelenak, post: 363035, member: 327 wrote: What baked my brain was that northings were positive and eastings negative.Completely opposite to the ...

Larry Scott, post: 365881, member: 8766 wrote: Gotta keep up. 20 years of revisions, miss a few memos and then ..."Consequently, rigorously speaking, ...

The NGA (or is it NGIA) has an interesting policy with respect to their WGS 84 coordinates. Since it does not include a provision for velocities, they...

I personally would go with Polaris over solar azimuths. Especially since you are not worrying about paying night differentials.I am confused by some c...

Thaddeus Vincenty was certainly a noteworthy geodesist. His solutions to the inverse and forward problems are still relevant today. Wikipedia has a ni...

Bill93, post: 365043, member: 87 wrote: In a thread a while back I learned that my education on State Plane Coordinates was incomplete in that older b...

The reason for non-government US attendees is budgetary. Most agencies have severely cut travel budgets. Foreign travel is often seen as a boondoggle....

Scott Zelenak, post: 364521, member: 327 wrote: 🙂 I wrote the 2001 recovery note. Obviously having too much spare time, I have chosen to be annoyi...

While you have made some interesting deductions from available data, the 2001 recovery indicates a different building now exists in the site.The reduc...

John Hamilton, post: 363925, member: 640 wrote: I agree that it is pricey. Nothing from ASCE is cheap (have you seen the dues?).But the information is...

I, for one, would never refer to mean sea level as a relevant datum. While the NGS definition of the geoid is something along the lines of: an equipot...

A little more information. Ellipsoid and dates of applicability of datums. This info was from an old PowerPoint presentation by the eminent Dave Doyle...

Your post indicates you were accessing USACE publications through a commercial site. Why not the link above and go to the official site?Do a search fo...

Not involved at all.