Update UT1 - UTC
UT1 - UTC (DUT1) is used to
convert from UTC to UT1. This is needed for pointing the
telescope. The Earth orientation dept. of the USNO publishes
the measured and predicted values for DUT1. There is usually about
1 year of data available.
A fit is done to the "future"
values and then used for the pointing. It is stored in the file :
Plots of the fit residuals show:
- Top: Black is the data and red is the fit.
- Center and bottom plots show the fit error in
mjd and date.
- 14sep18.ps (.pdf)
- Used data 14sep1 -> 30jun19
- 01dec17 (.ps) (.pdf)
- Used data 01dec17 -> 30nov18
- 01jan17 (.ps) (.pdf)
- leap second added 01jan17
- Used data 01jan17 thru 01dec17 for fit.
- 08dec15 (.ps) (.pdf)
- used 08dec15 -> 08dec16.. peak error 40ms .. rms 26 ms
- but at least i won't forget to redoit
- 01oct15 (.ps) (.pdf)
- used 01oct15 -> 15jun16 for fit
- this data was downloaded 22jun15
- --> be sure the pointing program gets restarted sometime
- 08dec15.. guess what.. pointing program hasn't been
restarted since 01oct15
- error got to be about .1 secs....
- 01jul15 (.ps) (.pdf)
- used 01jul15 -> 30sep15 for fit
- This data was downloaded 22jun15
- Used data 11jul14 -> 11jul15. downloaded 16jul14
- restarted pntprog on 29jul14 15:00 ast. This is when new
dut1 became active
- 21oct13 (.ps) (.pdf)
- Used data 21oct13 -> 15jun14. downloaded 21oct13
- 05jul13 (.ps) (.pdf)
- Used data 05jul13 -> 30sep13. downloaded 04jul13
- 01oct12 (.ps) (.pdf)
- used data downloaded jun12. data from 01oct12-jun13.
- 01jul12 (.ps) (.pdf)
- after leap second inserted 01jul12. Only fit jul12 thru
sep12 since curvature changes around sept12
- 28feb12 (.ps) (.pdf)
- data was loaded for 24feb12 thur 30jun12 (then a leap sec
will be installed).
- 19apr11 (.ps) (.pdf)
- data was loaded for 15apr11 thru 15apr12z and fit.
- 08feb10 (.ps) (.pdf)
- data was loaded for 08feb10 thru 04feb11 and fit.
- 13dec08 (.ps) (.pdf)
- data was loaded for 01jan09 thru 11dec09 and fit
- This is needed for the leap second on 01jan09
- 27nov07 (.ps) (.pdf)
- New data was loaded 27nov07 and refit.
- This is after the painting project and
before the new pointing model.
- 07dec06 (.ps)
- data was loaded 07dec06 thru 01jul07
- The fit was needed because the old fit was
no longer valid.
Most recent utcToUt1.dat file