Which gets real fun with things like solid earth tides getting involved. Lady Heather can now calculate and plot solid earth tides. Over the last 48 hours my place moved up/down 315 mm and gravity changed 186 microgals... and that was a rather stable period. ------------------ > A 1 meter change in elevation corresponds to a frequency offset of about 1e-16. So for 1e-18 levels of performance you "only" need to know g, or your elevation to 1 cm accuracy.

Mark... You're place really moved a foot in 48 hours? Impressive and scary! From Tom Holmes, N8ZM > On Dec 9, 2017, at 8:19 PM, Mark Sims <holrum@hotmail.com> wrote: > > Which gets real fun with things like solid earth tides getting involved. Lady Heather can now calculate and plot solid earth tides. Over the last 48 hours my place moved up/down 315 mm and gravity changed 186 microgals... and that was a rather stable period. > > ------------------ > >> A 1 meter change in elevation corresponds to a frequency offset of about 1e-16. So for 1e-18 levels of performance you "only" need to know g, or your elevation to 1 cm accuracy. > <tides.gif> > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there.

Is that a Trimble Thunderbolt? Is there a way to compute the uncertainties? On Sun, Dec 10, 2017 at 2:42 AM, Tom Holmes <tholmes@woh.rr.com> wrote: > Mark... > You're place really moved a foot in 48 hours? Impressive and scary! > > From Tom Holmes, N8ZM > >> On Dec 9, 2017, at 8:19 PM, Mark Sims <holrum@hotmail.com> wrote: >> >> Which gets real fun with things like solid earth tides getting involved. Lady Heather can now calculate and plot solid earth tides. Over the last 48 hours my place moved up/down 315 mm and gravity changed 186 microgals... and that was a rather stable period. >> >> ------------------ >> >>> A 1 meter change in elevation corresponds to a frequency offset of about 1e-16. So for 1e-18 levels of performance you "only" need to know g, or your elevation to 1 cm accuracy. >> <tides.gif> >> _______________________________________________ >> time-nuts mailing list -- time-nuts@febo.com >> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. > > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there.

Check https://en.wikipedia.org/wiki/Earth_tide According to that, a foot of motion is easily plausible. The Wiki article says that displacements around a meter in the solid crust can be seen over the right intervals. This must wreak havoc in VLBI geodesy work, except that for some in the field this would be the "signal" and most everything else the noise. Dana On Sat, Dec 9, 2017 at 7:42 PM, Tom Holmes <tholmes@woh.rr.com> wrote: > Mark... > You're place really moved a foot in 48 hours? Impressive and scary! > > From Tom Holmes, N8ZM > > > On Dec 9, 2017, at 8:19 PM, Mark Sims <holrum@hotmail.com> wrote: > > > > Which gets real fun with things like solid earth tides getting > involved. Lady Heather can now calculate and plot solid earth tides. > Over the last 48 hours my place moved up/down 315 mm and gravity changed > 186 microgals... and that was a rather stable period. > > > > ------------------ > > > >> A 1 meter change in elevation corresponds to a frequency offset of > about 1e-16. So for 1e-18 levels of performance you "only" need to know g, > or your elevation to 1 cm accuracy. > > <tides.gif> > > _______________________________________________ > > time-nuts mailing list -- time-nuts@febo.com > > To unsubscribe, go to https://www.febo.com/cgi-bin/ > mailman/listinfo/time-nuts > > and follow the instructions there. > > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/ > mailman/listinfo/time-nuts > and follow the instructions there. >

Hi Just as there are Time Nuts, there are Tide Nuts (I suppose it’s capitalized …). There is a a lot of data out there on just what sort of solid tides one might see at this or that point. Bob > On Dec 10, 2017, at 7:29 AM, Azelio Boriani <azelio.boriani@gmail.com> wrote: > > Is that a Trimble Thunderbolt? Is there a way to compute the uncertainties? > > On Sun, Dec 10, 2017 at 2:42 AM, Tom Holmes <tholmes@woh.rr.com> wrote: >> Mark... >> You're place really moved a foot in 48 hours? Impressive and scary! >> >> From Tom Holmes, N8ZM >> >>> On Dec 9, 2017, at 8:19 PM, Mark Sims <holrum@hotmail.com> wrote: >>> >>> Which gets real fun with things like solid earth tides getting involved. Lady Heather can now calculate and plot solid earth tides. Over the last 48 hours my place moved up/down 315 mm and gravity changed 186 microgals... and that was a rather stable period. >>> >>> ------------------ >>> >>>> A 1 meter change in elevation corresponds to a frequency offset of about 1e-16. So for 1e-18 levels of performance you "only" need to know g, or your elevation to 1 cm accuracy. >>> <tides.gif> >>> _______________________________________________ >>> time-nuts mailing list -- time-nuts@febo.com >>> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>> and follow the instructions there. >> >> _______________________________________________ >> time-nuts mailing list -- time-nuts@febo.com >> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there.