Luke Coletti wrote:
Fer,
You mention above that for 12-26 there is a variation in the
EoT
between -9 and -46 seconds, a 37 sec delta, over a four year period.
Which
4 year period did you calculate for? I have calculated and included
below
both the solar day length and EoT values for 12-26 over a twenty year
period. The max delta between succeeding EoT values and the 1995
value,
column G, over the twenty year period reaches 23.5 secs in 2012. It
can also
be seen that on periods of four years from the starting point in 1995
the
delta reaches only 1.6 secs after twenty years! I used the 1995 USNO
formulas as listed in section C page 24. Perhaps you can let me know
which
methods you used to calculate the 37 sec delta and over what period.
Regards,
Luke Coletti
<snip....>
Luke,
I answered your e-mail, but something went wrong with sending it and I
don't have a copy anymore.
So I start again.
I have to admit I made a (typing?) error in my e-mail.
The value -9 sec. is false.
I calculated the EoT with my program equadecl.
The values are for 12:00 UT.( accuracy + or - 5 sec. I think)
1996 : -46 sec.
1997 : -38 sec.
1998 : -31 sec.
1999 : -24 sec.
2000 : -46 sec.
The difference in a 4 years period is 22 sec., about the same as you
calculated.
Sorry for my error in my earlier e-mail.
