[time-nuts] time-nuts Digest, Vol 35, Issue 26

James R Miller james at jrmiller.demon.co.uk
Sun Jun 10 20:02:36 UTC 2007


PRIVATE MESSAGE - OFF LIST
==========================

On 10 Jun time-nuts-request at febo.com wrote:

> Is there some way to get TT to better than a tenth of a second,
> or is the earth just too sloppy of a time keeper?

Dear Brooke,

For once, the Earth's spin doesn't enter into it.

  TT = TAI + 32.184s
  
You can get TAI from

  TAI = UTC + 33s
  
The "32.184s" was fixed when UTC/TAI was invented.  The "33s" you can get from
IERS Bulletin-A.  It changes whenever there is a leap second, but so too does
UTC, and TAI thus remains continuous.

http://maia.usno.navy.mil/ser7/ser7.dat

TT is the independent variable of astronomical ephemerides.

With best wishes.

-- 
==========================================================================
    James R Miller      WWW/PGP:     http://www.jrmiller.demon.co.uk/
  Cambridge, England   Stardate:        2007 Jun 10 [Sun] 1951 utc
==========================================================================




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