Never heard of it, but stumbled across it this morning.
Anybody have any guesses, because I don't.
I'm sure it isn't the first thing that pops into my mind...at least I hope not.
U. S. Board of Surveys or typo which might have been USGS?
What about the "USSD" on the following line? I don't recognize that either...
USSD is United States Standard Datum, which later became North American Datum 1913 without any definition change.
USBS I've now found on several older stations, so it's not a misprint.
USBS is a newer datum that allows you to connect it to your computer without rebooting, unlike the old USC&GS datum.
Yeah, that's probably it.... :snarky:
Here are US (Conus) Datums according to the dsdata.txt file link which can be found on the NGS datasheet:
US (CONUS) DATUMS:
ABBREVIATION DEFINITION
USBS BESSEL SPHEROID
USCA CALIFORNIA STANDARD DATUM
USCC CAMP COLONA 1890 DATUM
USCH CHARLESTON AND SAVANNAH DATUM
ELPS EL PASO DATUM
USIA INDEPENDENT ASTRO DATUM 1880
MORC MISSOURI RIVER COMMISSION DATUM
USNO NEW ORLEANS MOBILE DATUM
USSD US STANDARD DATUM
USVN VICKSBURG NATCHEZ DATUM
Ah. Then it should be below USSD as its older. Makes sense now.
Thanks.
Now if NGS would just finish the USSD to NAD 83 conversion they are working on in the new NADCON my life would be a lot easier.
A little more information. Ellipsoid and dates of applicability of datums. This info was from an old PowerPoint presentation by the eminent Dave Doyle.
BESSEL 1841 --------------
LOCAL ASTRO DATUMS (1816-1879)
CLARKE 1866
NEW ENGLAND DATUM (1879-1901)
U.S. STANDARD DATUM (1901-1913)
NORTH AMERICAN DATUM (1913-1927)
NORTH AMERICAN DATUM OF 1927