[LEAPSECS] IERS Message No. 180: Revision of IERS Earth Rotation Series effective 1 February 2011

[Poul-Henning Kamp]

In message <371BE82A03680E4087F343D5C9883D8D112403 at FS029EXCH.bkg>, central_bure
au at iers.org writes:


>************************************************************************

>IERS Message No. 180                                    January 05, 2011

>************************************************************************

>

>Revision of IERS Earth Rotation Series effective 1 February 2011

>

>[...]

>

>   2) Changes in UT1-TAI and celestial pole offsets are respectively on

>      the order of 2 s, 1, and 17 as which are at the level of the WRMS

>      between IVS individual solutions.


TAI is supposed to be a "uniform atomic timescale", so I cannot
imagine they would have stuck/removed two seconds from it because
the figured out better params for Earth orientation.

Unless to reinforce that people should not use it for anything ?

Jumping UT1 by two seconds, would send DUT >1s, possibly >2s depending
on the signs.

The transition date is 2011-02-01.

I believe we should have seen Bul-C for 2011-06-31 already (six months
notice, remeber ?) but they usually run two weeks late.

So are we set for 4 months of DUT>1s or 4 months DUT>2s + 6 months
DUT>1s now ?

Can somebody explain this ?

Rationally ?

Poul-Henning

Not updated:
	http://hpiers.obspm.fr/eop-pc/earthor/utc/TAI-UTC_tab.html

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