On 3/23/08 9:48 AM, in article 3dtFj.8403$9O.6833@[EMAIL PROTECTED]
"Judson McClendon" <judmc@[EMAIL PROTECTED]
> wrote:
> "winston19842005" <bjjlyates@[EMAIL PROTECTED]
> wrote:
>> "Judson McClendon" <judmc@[EMAIL PROTECTED]
> wrote:
>>>
>>> It is unlikely that the Gregorian Calendar will remain unchanged past
year
>>> 4000 or so, because of ***ulative divergence from the solar year, and
by
>>> year 4000 it will be whole day off. There have already been attempts
to
>>> correct the divergence by changing the leap year rule. The current
rule is
>>> "If year is MOD 4 then it's a leap year, unless it's MOD 100 then it
isn't,
>>> unless it's MOD 400 then it is." The new rule would add "unless it's
MOD
>>> 4000 then it isn't."
>>
>> Perhaps by then we will correct the REAL problem, by correcting the
speed of
>> this planet's orbit?
>>
>> Would it be preferable to make it exactly 365 days? Or maybe, let's
make it
>> 100 - easier to figure...
>
> It's not just that the year is longer than 365.2425 days, it's that the
year
> is
> gradually getting longer from gravitational effects like tidal friction
and
> orbital perturbations from Jupiter. Assuming technology to set the
Earth's
> orbit at exactly 365 days, it would still have to be periodically
adjusted.
> Setting the orbit at 100 days would require an orbit too near the sun
(we
> would roast) or lengthening the day to 87.6 hours. Neither sounds very
> desirable, just to have an even length of year. :-) Most of the .7C
increase
> in global temperatures claimed over the last century is now known to be
> due to a very slight increase in solar radiation during the first half
of that
> period. Can you imagine the drastic effects from moving the Earth closer
> to the sun? :-)
>
> The rotation of the Earth is also slowing. Have you noticed how many
> leap seconds have been added in recent years? This will increase over
> time. Most of this is due to tidal friction from the Moon and Sun.
I remember reading that the drag effect was slowing down our movement
around
the Sun.
Yes, I realize the effect of 100 day orbit! ;)
I remember an old BASIC that allowed you to pick a star or pick a star
type,
then you were allowed to pick the particulars of your planet and it would
tell you the probability of life and other particulars.
I think it was called "World Builder". Still have it on an old TI 5.25"
floppy. Do you remember that? I cannot remember where it came from. Maybe
TRS-80, since my friend who translated it was heavily into those. Google
comes up with way too many hits...
I'm sure if you looked at it closely today, you could pick its "science"
apart, but it was fun at the time!
|
