Re: Earth's dimensions

On Jul 22, 5:21 am, oriel36 <kelleher.ger...@xxxxxxxxx> wrote:
On Jul 22, 12:24 pm, Jim Willemin <jim***willemin@hot***mail.com>
wrote:





oriel36 <kelleher.ger...@xxxxxxxxx> wrote innews:50c5a936-959d-4680-8cdc-bd1d19f56450@xxxxxxxxxxxxxxxxxxxxxxxxxxxx:

The Earth's Equatorial circumference is 40,075 km which yields 111.32
km per geographical degree and 1669.8 km per 15 degrees -

http://www.ncgia.ucsb.edu/education/curricula/giscc/units/u014/tables/
t
able02.html

At the Equator there is a rapid transition from daylight to darkness
as the Earth turns at 111.32 km every 4 minutes/1 degree while at 60
degrees latitude there is a longer transition to darkness (twilight)
as the Earth turns a slower 55.80 km every 4 minutes/1 degree.

As the Earth turns 1669.8 degrees for 15 degrees/1 hour of rotation,it
is remarkable to see an alternative 1674.4 km value given for rotation
in 1 hour -

"Want to do the calculation for yourself? The circumference of the
Earth at the equator is 40,075 km. And the length of time the Earth
takes to complete one full turn on its axis is 23.93 hours. So
40,075/23.93 = 1,675 km"

http://www.universetoday.com/guide-to-space/earth/how-fast-does-the-
ear
th-rotate/

If 15 degrees of geography and rotation yielded 1675 km then the total
Equatorial circumference would be a nonsensical 40200 km or 125 km in
excess of the actual 40,075 km value.No offence to the ee guys but
geologists are stuck with one of the worse breaches of reasoning which
has its roots in the late 17th century which makes it impossible to
work with planetary dynamics or even global geography and geology.

I know it is an exercise in futility to introduce reality into this
conversation, but:

What reality !,you are arguing against a geometric certainty which
determines the Earth turns once in 24 hours or 15 degrees per hour,you
may not appreciate the technical effort which makes it that way but
this is why it is many,many time worse than those who deny that men
landed on the moon as a simple fact with an enormous amount of effort
behind it.

You seem to forget that the earth orbits the sun, and that the
tangential velocity due to the earth's rotation needs must be calculated
from an external, non-rotating frame of reference.

I forget nothing,I know the technical arguments inside out and nobody
has made the effort to match the historical insights which reference
daily rotation to natural noon and the orbital motion to the
background stars.Learning why rotation through 360 degrees is 24 hours
is also an exercise in understanding how the 24 hours of Monday turn
into the 24 hours of Tuesday ect,why the calendar system allows a
linear progression of years out of a raw orbital cycle,how twilight
length is extremely short  at the Equator and  longer towards the
geographical poles corresponding to slower speeds and many other
lovely insights of us to everyone when they accept the 24 hour value.

 Such a reference

frame is provided by the stars.  I'm sure you will have observed that
through the course of a year the sun appears to move against the
background of the distant stars at roughly 1 degree per day as a
consequence of the earth orbiting the sun.  Thus, using the average time
from consecutive meridian transits of the sun to calculate the speed of
the earth's rotation will be in error, since the earth needs to turn
just a little less than 361 degrees between successive 'noons' in order
to account for the yearly travel of the sun.  

That is late 17th century contrived junk based on inverting the
references for daily and orbital motions,something which John
Flamsteed came up with .

The actual system is based on the observation of natural noon,the
creation of the 24 hour day from that observation and subsequently
each 24 hour day moves constantly into the next 24 hour day -

"Here take notice, that the Sun or the Earth passeth the 12. Signes,
or makes an entire revolution in the Ecliptick in 365 days, 5 hours 49
min. or there about, and that those days, reckon'd from noon to noon,
are of different lenghts; as is known to all that are vers'd in
Astronomy. Now between the longest and the shortest of those days, a
day may be taken of such a length, as 365 such days, 5. hours &c. (the
same numbers as before) make up, or are equall to that revolution: And
this is call'd the Equal or Mean day, according to which the Watches
are to be set; and therefore the Hour or Minute shew'd by the Watches,
though they be perfectly Iust and equal, must needs differ almost
continually from those that are shew'd by the Sun, or are reckon'd
according to its Motion. But this Difference is regular, and is
otherwise call'd the Aequation"

http://www.xs4all.nl/~adcs/Huygens/06/kort-E.html

The magnificent trick which astronomers used was to realise that as
each average 24 hours day turns into the next 24 hour day,they could
transfer the 'average' part to daily rotation as a constant so that
the incremental values that equalise natural noon to the 24 hour day
also keeps rotation constant by the same measure so that 1 degree of
rotation equates to 4 minutes of clock time,15 degrees per hour and 24
hours of rotation through 360 degrees.

If you repeat your

calculations accurate to six significant figures, you will discover that
in one 24 hour period a point on the earth's equator will travel
40,184.7 km, or just a hair shy of 361 degrees.

The table of values represent 1 degree of geography and 4 minutes of
clock time -

http://www.ncgia.ucsb.edu/education/curricula/giscc/units/u014/tables...

The Equatorial value of 111.32 km is expanded to 1669.8 km for 15
degrees and 40,075 km for 24 hours.A person at the Equator experiences
a rapid transition from daylight to darkness as the Equator turns at a
rapid 1669.8 km /hour into the orbital shadow while a person at 60
degree latitude will experience a longer transition from daylight to
darkness (twilight) as his location turns at a slower  837 km per
hour.

 This is exactly how far

it needs to travel to get the sun from one meridian transit to another,
considering that the sun is moving eastward against the background of
distant stars at 0.98 degrees per day (on average - it varies because of
the eccentricity of Earth's orbit and resulting variation in orbital
velocity).- Hide quoted text -

The late 17th century 'sidereal vs solar time' hoax is so crude that I
can't believe people refuse to work it out themselves for they assume
that the Earth rotates to noon every 24 hours -

360 degrees = 24 hours
 1 degree = 4 minutes
.986 degree = 3 minutes 56 seconds

24 hours minus 3 minutes 56 seconds = 23 hours 56 minutes 04 seconds.

http://astrosun2.astro.cornell.edu/academics/courses//astro201/sidere...

Again,should people feel revulsion at those who deny that men landed
on the moon and the enormous effort behind that simple fact ,they
should equally feel much more revulsion for the loss of basic
planetary facts of shape,dimensions and rotational characteristics
which is summed up in the 24 hour/360 degree value for daily rotation.

To explain the twilight effect where people at Equatorial regions
experience a rapid transition from daylight to darkness while those in
temperate latitudes experience a  longer transition due to the
rotation of the Earth and the different rotational speeds as the Earth
is a rotating sphere,the only acceptable values are those in the
tables -

http://www.ncgia.ucsb.edu/education/curricula/giscc/units/u014/tables...

The Earth rotates 111.32 km per degree at the Equator, 1669.8 km per
15 degrees and the entire Equatorial circumference of  40,075 km
through 360 degrees .

Feckwit (Oriel36) is incapable of answering simple questions,
especially those that only require a YES or a NO answer. To do so
would eventually lead to the unraveling of his wispy and tenuous
theories, which the rest of us already know are 100% inaccurate.

Feckwit is all alone with his theories, he has not found a single
professional who agrees with him. Because of this, he reasons that he
must be superior to literally all of the great scientific minds of
both the past and the present.

Even in the face of STRONG CONTRADICTORY EVIDENCE to his theories,
Feckwit will only regurgitate endless quotes of dead astronomers,
which he doesn't actually understand or interpret correctly, as
evidence for them.

Feckwit is no astronomer, just as he is no climatologist, no
anthropologist, no mathematician, or no geologist, but this does not
stop him from spouting non-stop drivel, day after day.

Many have tried to explain basic celestial mechanics to Feckwit in
simple, easy-to-understand terms, but he either doesn't read these
posts or doesn't have the capacity to understand them. Instead, he
responds to such posts by essentially starting all over again, from
the top, with the same old worn-out arguments that my 14-year-old
granddaughter can blow out of the water with one swat. I have to give
him credit, he carries on undeterred, and unconvinced that there is
ever any possibility that that he is even slightly in error.

Unlike the majority of us, Feckwit has never learned anything here,
and only in rare cases does he agree with anyone at all. It seems to
me that whenever an interesting thread is started, it is soon
disrupted by you-know-who's venomous desultory philippic, and the
whole thing is hijacked for good. Not this thread, of course, he
started this one himself.

Arguing with Feckwit is like hitting your head against the wall in
that it feels pretty good when you finally stop doing it. Disagreeing
with Feckwit is quite fruitless, he is not at all receptive to
friendly instruction, and often counters by calling you names, and
that is too bad, because there are (and were) a lot of really smart
people here who have a lot to offer the rest of us, and jerks like
Feckwit drive them away. Maybe he requires everyone's attention all of
the time.

Feckwit wouldn't last 2 minutes on any moderated forum, and in that I
find immense satisfaction.

"Life's tough......it's even tougher if you're stupid."
- John Wayne

"Talk sense to a fool and he calls you foolish."
- Euripides
.

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