NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Andr?s Ruiz
Date: 2004 Jul 27, 16:20 +0200
| I E R S B U L L E T I N - A |
| http://maia.usno.navy.mil/ |
| Delta T = 32.184 s + (TAI - UTC) - (UT1 - UTC) |
| 2004 [ser7.dat] |
| (TAI - UTC) = 32 s |
| DUT1= (UT1-UTC) = -0.5 s |
| Delta T = 64.684 |
-----Mensaje original-----
De: Navigation Mailing List [mailto:NAVIGATION-L@LISTSERV.WEBKAHUNA.COM]
En nombre de George Huxtable
Enviado el: martes, 27 de julio de 2004
10:52
Para: NAVIGATION-L@LISTSERV.WEBKAHUNA.COM
Asunto: Re: [NAV-L] no
leap second coming in December
On 24 July Paul Hirose
wrote-
>A few days ago the IERS announced there would be no leap
second at the
>end of this year. We will have a record-setting run of six
consecutive
>years with no leap second. The previous longest break was
1986 and
>1987.
>
>At present UT1 is .46 second behind UTC.
The offset is predicted to be
>.49 second at the end of the year, and .52
second in mid-2005.
Does this imply, then, that delta-T, the difference
between universal time and ephemeris time, has remained "stuck" at a constant,
or nearly-constant value, over that period of six years? If so, what vaue has it
stuck at?
And if so, does anyone understand the geophysical causes that
have resulted in the slowing of the Earth's rotation, which has been so
consistent over the last 80 years or so, to suddenly switch off, 6 years
ago?
Or have I misunderstood something
completely?
George.
================================================================
contact
George Huxtable by email at george@huxtable.u-net.com, by phone at 01865 820222
(from outside UK, +44 1865 820222), or by mail at 1 Sandy Lane, Southmoor,
Abingdon, Oxon OX13 5HX, UK.
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