Last seen: April 9, 2026 5:20 pm
Leap seconds used to be more often. It used to be harder to keep track of them. Notice the hiatus from '99 to '05
ekmanspiral, post: 405238, member: 3512 wrote: I thought it was the tidal currents hitting the mid-oceanic ridges that was slowing down the rotation.T...
ekmanspiral, post: 405238, member: 3512 wrote: I thought it was the tidal currents hitting the mid-oceanic ridges that was slowing down the rotation. ...
Jim in AZ, post: 402935, member: 249 wrote: Apparently the earth is not cooperating properly so there is a leap second being added at the end of the y...
John Hamilton, post: 403125, member: 640 wrote: Nobody mentions my favorite distance, which is mark to mark (which is a slant range). It is the only o...
The drawback or craziness, as was pointed out, there's no way tell the relationship of 2 three-word identifiers. In other words, how far is 'holly.sug...
That is previous. I would like to a GPS baseline, direct measure between them. That would be interesting. I also like that all of the descriptions in ...
BM JV3199. Chiseled square in granite window sill in the Hagerstown MD courthouse. Established Oct 1877, USCS. Found as described.What makes this BM s...
7 ppm by chain, I mean, metal analog, really high skill then. And now.
I saw a job posting for chainman.I suppose the job is really for reflector-pole-man.
Surveying is an old science and art. So its terminology should retain tradition.And 'chaining' as task, or procedure, doesn't have to describe the arc...
Division of National Mapping. Australia From field practices manual:1.18 Field Chaining1.18.1 ChainsMost third order chaining has been done with the 3...
well, just figure the azimuth from House to a leg of the net, and hold that bearing fixed. It's exactly the same. House has served its purpose for the...
I believe he's using an assumed position. i.e., he has no control. So, fixing one point and one azimuth (minimally constrained) is all he has.
Convert Geo az to VT SPC, grid az. Geo azimuth is in the output, and Geo to SPC is one step.
If you ignore the 04-Jun obs, there's only 1.1" spread in four observations to average. It won't matter much. And a star shot returning so close a val...
If you consider pre GPS, pre EDM, and you had to determine a position by resection, from points 20-50K feet, or more, away, you'd need a true subsecon...
And how good were the ephemerides back then?
In long distance control surveys, 1" is a must. When your average leg can be a mile, and 3-5 mile legs, a second here and there can add up. However, t...
MightyMoe, post: 381579, member: 700 wrote: If the numbers were close, then you would know the original longitude was a mistake I don't even know wha...