Most people when they wake up at dawn understand that the Sun rising and setting within each 24 hour period represents a rotation of our home planet while few people go into greater detail to comprehend the Lat/Long system overlaid on the geometry and geography of the Earth and tied to each rotation in 24 hours . Nobody goes into the details of planetary dynamics where the system which differentiates the rotation of the Earth 365 1/4 times per annual circuit from human timekeeping which formats the natural observation into the 365 day/366 day calendar framework.

We exist in an era where it is fashionable to say that the Earth turns 366 1/4 times within the confines of an orbital circuit thereby destroying the elegant reasoning which links timekeeping to the great planetary cycles of daily rotation and orbital motion -

"During one orbit around the Sun, the Earth rotates about its own axis 366.26 times" Main 'Earth' page, Wikipedia

http://en.wikipedia.org/wiki/Earth

Effectively people are prepared to believe that days and rotations fall out of step across an annual circuit which should be unthinkable for reasonable people let alone those involved in navigation and a familiarity with the Lat/Long system. How mistakes were made to give rise to a monstrous reasoning is second to understanding how the timekeeping system framework was constructed from observations of the Earth's motion and the parent observation that there are 1461 rotations within 4 orbital circuits which breaks down to 365 1/4 rotations per orbital circuit.

It is a question of relevance at this stage, how people value their own intellectual capabilities at the most basic level where they know that when they wake up to a new day they are also waking up to another rotation and they never,ever fall out of step.

The quite understand the silence regarding this awful notion that there are 366 1/4 rotations inside an orbital circumference when,in fact, there are 365 1/4 with the latter correct value drawn from the parent observation of the additional February 29th rotation and what it represents in dynamical terms.

About 20 years ago anyone who picked up a textbook would have read that the Earth doesn't turn once in 24 hours but in 23 hours 56 minutes 04 seconds -

http://hypertextbook.com/facts/1999/JennyChen.shtml

The idea was that the extra 3 minutes 56 seconds to 24 hours accumulates over an orbital period and that generates the extra rotation than 24 hour days -

"During one orbit around the Sun, the Earth rotates about its own axis 366.26 times" Wikipedia main 'Earth' article

Like all catastrophic events where considerable damage and chaos ensues, the consequences are brutal including the inability to react to this situation where the emergence of the Lat/Long system in tandem with the 24 hour system keeps days and rotations in sync.

Today they even have created a new fiction conjured out of thin air in order to create a division between timekeeping and the rotation of the Earth where they now reject the 'solar vs sidereal' fiction and introduce a non cyclical and non astronomical assertion -

"At the time of the dinosaurs, Earth completed one rotation in about 23 hours," says MacMillan, who is a member of the VLBI team at NASA Goddard. "In the year 1820, a rotation took exactly 24 hours, or 86,400 standard seconds.." NASA

I hope reader here enjoyed the brief tour through to the historical and astronomical origins of timekeeping even in an era where men no longer believe that 24 hour days and rotations keep in step. Astronomy today is basically rudderless - an exercise in voodoo and bluffing created by academics and for academics while basic facts and enjoyable principles are ignored and even despised.

There was a mention in this thread about burning at the stake for believing the Earth goes around the Sun referring to the Catholic Church and the events surrounding the Galileo affair. The real problem and valid objection of the Pope was how to prove the Earth turns using the same system which predicts astronomical events in that he believed it couldn't be done, at least according to a closer inspection of the issues separating Galileo and the Pope -

"Here lurked the danger of serious misunderstanding. Maffeo Barberini, while he was a Cardinal, had counselled Galileo to treat Copernicanism as a hypothesis, not as a confirmed truth. But 'hypothesis' meant two very different things. On the one hand, astronomers were assumed to deal only with hypotheses, i.e. accounts of the observed motions of the stars and planets that were not claimed to be true. Astronomical theories were mere instruments for calculation and prediction, a view that is often called 'instrumentalism'.. On the other hand, a hypothesis could also be understood as a theory that was not yet proved but was open to eventual confirmation. This was a 'realist' position. Galileo thought that Copernicanism was true, and presented it as a hypothesis, i.e. as a provisional idea that was potentially physically true, and he discussed the pros and cons, leaving the issue undecided. This did not correspond to the instrumentalist view of Copernicanism that was held by Maffeo Barberini and others. They thought that Copernicus' system was a purely instrumental device, and Maffeo Barberini was convinced that it could never be proved. This ambiguity pervaded the whole Galileo Affair."

http://www.unav.es/cryf/english/newlightistanbul.html

The parent observation of timekeeping where it meshes with planetary dynamics is with the leap day rotation and the 1461 rotations which fit inside 4 orbital circumferences. This fact goes in two separate directions - for interpretative astronomy where the Earth's motions and solar system structure is being researched and proved it reduces to 365 1/4 rotations per orbital circuit while for predictive astronomy where astronomical events are determined within the calendar framework the parent 1461 rotations are formatted in a 365/366 rotation scaffolding.

Sure,people can believe that Church doctrine was dependent on the Earth at the center of the Universe however a closer look at the issue reveals that the objections were quite valid. Only with 21st century tools can the issue be untangled and resolved but it can't be if contemporaries believe the Earth rotates 366 1/4 times inside one orbital circuit.

The Lat/Long system plays a crucial role in extracting humanity from an era mired in voodoo and bluff including the fuss over a 'leap second' -

http://www.abc.net.au/news/2015-01-0...r-year/6002002

On Saturday, 3 January 2015 13:36:04 UTC-4, wrote:
On Sat, 3 Jan 2015 08:14:26 -0800 (PST),
wrote:

This is the broadest possible overview for those who are unfamiliar with how the motions of the Earth fit in with human timekeeping and although it is an injustice to those people who created the system we use today, the overview is much better than none at all. There is no stopping to differentiate between the original geocentric astronomers and their observations from the later heliocentric astronomers who worked off the idea that the Earth moves between Venus and Mars around the Sun so readers today don't concern themselves with the level of knowledge of any given era as this will be taken for granted in order to move the story along.

As the Earth moves through space in its circuit around the Sun,certain stars lying on or near the same plane as the Earth's orbital motion are temporarily lost behind the Sun's glare. The older astronomers marked the passage as the Sun through the constellations (hence birth signs) but for purposes of this story it is better to consider the apparent motion of the stars behind the Sun due to the orbital motion of the Earth -

https://www.youtube.com/watch?v=eeQwYrfmvoQ

The anchor for the Lat/Long system originally was based on the appearance of one particular star as the orbital motion of the Earth placed the star just far enough to one side of the Sun one morning, That star was the brightest one in the celestial arena known as Sirius and can be seen on the bottom left of the image -

https://www.youtube.com/watch?v=eeQwYrfmvoQ

".. on account of the procession of the rising of Sirius by one day in the course of 4 years,.. therefore it shall be, that the year of 360 days and the 5 days added to their end, so one day shall be from this day after every 4 years added to the 5 epagomenae before the new year" Canopus Decree 238 BC

Unbeknownst to themselves, what the Egyptians were actually doing was defining the Earth's orbital position around the Sun using the seasonal appearance of a star as a gauge and the number of rotations that fit inside an orbital circuit, in this case 1461 rotations for 4 orbital circuits which breaks down into 365 1/4 rotations to one orbital circuit.

This is the founding principle where one 24 hour day keeps in step with one rotation of the Earth and the basis of the Lat/Long system along with the reason why the extra day and rotation is introduced in order to keep the Earth's position in space fixed by the number of rotations,at least to the nearest rotation.

The next step is the process which equates the 'average' 24 hour day with 'constant' rotation insofar as the average 24 hour day substitutes for constant rotation through 360 degrees in that period.






I am reacquainting myself with celestial mechanics as I am playing
with my new sextant.


I've thought about buying the Davis 25 plastic sextant to play with. one practical use would be to confirm the height of the huge Linden trees that border my back yard.
I did a google search and found a link that described how you could estimate height with an upside down protractor, a string with a weighted object as a kind of plumb bob and a ruler to sight along.The ruler would sit on the upside down base of the protractor and the string would give you the sighted angle. The guy provided the formula to get a fairly accurate height.

On 1/8/2015 11:05 AM, True North wrote:
On Saturday, 3 January 2015 13:36:04 UTC-4, wrote:
On Sat, 3 Jan 2015 08:14:26 -0800 (PST),
wrote:

This is the broadest possible overview for those who are unfamiliar with how the motions of the Earth fit in with human timekeeping and although it is an injustice to those people who created the system we use today, the overview is much better than none at all. There is no stopping to differentiate between the original geocentric astronomers and their observations from the later heliocentric astronomers who worked off the idea that the Earth moves between Venus and Mars around the Sun so readers today don't concern themselves with the level of knowledge of any given era as this will be taken for granted in order to move the story along.

As the Earth moves through space in its circuit around the Sun,certain stars lying on or near the same plane as the Earth's orbital motion are temporarily lost behind the Sun's glare. The older astronomers marked the passage as the Sun through the constellations (hence birth signs) but for purposes of this story it is better to consider the apparent motion of the stars behind the Sun due to the orbital motion of the Earth -

https://www.youtube.com/watch?v=eeQwYrfmvoQ

The anchor for the Lat/Long system originally was based on the appearance of one particular star as the orbital motion of the Earth placed the star just far enough to one side of the Sun one morning, That star was the brightest one in the celestial arena known as Sirius and can be seen on the bottom left of the image -

https://www.youtube.com/watch?v=eeQwYrfmvoQ

".. on account of the procession of the rising of Sirius by one day in the course of 4 years,.. therefore it shall be, that the year of 360 days and the 5 days added to their end, so one day shall be from this day after every 4 years added to the 5 epagomenae before the new year" Canopus Decree 238 BC

Unbeknownst to themselves, what the Egyptians were actually doing was defining the Earth's orbital position around the Sun using the seasonal appearance of a star as a gauge and the number of rotations that fit inside an orbital circuit, in this case 1461 rotations for 4 orbital circuits which breaks down into 365 1/4 rotations to one orbital circuit.

This is the founding principle where one 24 hour day keeps in step with one rotation of the Earth and the basis of the Lat/Long system along with the reason why the extra day and rotation is introduced in order to keep the Earth's position in space fixed by the number of rotations,at least to the nearest rotation.

The next step is the process which equates the 'average' 24 hour day with 'constant' rotation insofar as the average 24 hour day substitutes for constant rotation through 360 degrees in that period.






I am reacquainting myself with celestial mechanics as I am playing
with my new sextant.


I've thought about buying the Davis 25 plastic sextant to play with. one practical use would be to confirm the height of the huge Linden trees that border my back yard.
I did a google search and found a link that described how you could estimate height with an upside down protractor, a string with a weighted object as a kind of plumb bob and a ruler to sight along.The ruler would sit on the upside down base of the protractor and the string would give you the sighted angle. The guy provided the formula to get a fairly accurate height.


You haven't mastered left, right, up, and down yet. You aren't ready for
a sextant yet.

--


I don't need anger management. I just need people to stop ****ing me off!
Respectfully submitted by Justan

True North wrote:
On Saturday, 3 January 2015 13:36:04 UTC-4, wrote:
On Sat, 3 Jan 2015 08:14:26 -0800 (PST),
wrote:

This is the broadest possible overview for those who are unfamiliar
with how the motions of the Earth fit in with human timekeeping and
although it is an injustice to those people who created the system we
use today, the overview is much better than none at all. There is no
stopping to differentiate between the original geocentric astronomers
and their observations from the later heliocentric astronomers who
worked off the idea that the Earth moves between Venus and Mars around
the Sun so readers today don't concern themselves with the level of
knowledge of any given era as this will be taken for granted in order
to move the story along.

As the Earth moves through space in its circuit around the Sun,certain
stars lying on or near the same plane as the Earth's orbital motion are
temporarily lost behind the Sun's glare. The older astronomers marked
the passage as the Sun through the constellations (hence birth signs)
but for purposes of this story it is better to consider the apparent
motion of the stars behind the Sun due to the orbital motion of the Earth -

https://www.youtube.com/watch?vîQwYrfmvoQ

The anchor for the Lat/Long system originally was based on the
appearance of one particular star as the orbital motion of the Earth
placed the star just far enough to one side of the Sun one morning,
That star was the brightest one in the celestial arena known as Sirius
and can be seen on the bottom left of the image -

https://www.youtube.com/watch?vîQwYrfmvoQ

".. on account of the procession of the rising of Sirius by one day in
the course of 4 years,.. therefore it shall be, that the year of 360
days and the 5 days added to their end, so one day shall be from this
day after every 4 years added to the 5 epagomenae before the new year"
Canopus Decree 238 BC

Unbeknownst to themselves, what the Egyptians were actually doing was
defining the Earth's orbital position around the Sun using the seasonal
appearance of a star as a gauge and the number of rotations that fit
inside an orbital circuit, in this case 1461 rotations for 4 orbital
circuits which breaks down into 365 1/4 rotations to one orbital circuit.

This is the founding principle where one 24 hour day keeps in step with
one rotation of the Earth and the basis of the Lat/Long system along
with the reason why the extra day and rotation is introduced in order
to keep the Earth's position in space fixed by the number of
rotations,at least to the nearest rotation.

The next step is the process which equates the 'average' 24 hour day
with 'constant' rotation insofar as the average 24 hour day substitutes
for constant rotation through 360 degrees in that period.






I am reacquainting myself with celestial mechanics as I am playing
with my new sextant.


I've thought about buying the Davis 25 plastic sextant to play with. one
practical use would be to confirm the height of the huge Linden trees
that border my back yard.
I did a google search and found a link that described how you could
estimate height with an upside down protractor, a string with a weighted
object as a kind of plumb bob and a ruler to sight along.The ruler would
sit on the upside down base of the protractor and the string would give
you the sighted angle. The guy provided the formula to get a fairly accurate height.

Basic geometry.

On 1/8/2015 12:13 PM, Justan Olphart wrote:
On 1/8/2015 11:05 AM, True North wrote:
On Saturday, 3 January 2015 13:36:04 UTC-4, wrote:
On Sat, 3 Jan 2015 08:14:26 -0800 (PST),
wrote:

This is the broadest possible overview for those who are unfamiliar
with how the motions of the Earth fit in with human timekeeping and
although it is an injustice to those people who created the system
we use today, the overview is much better than none at all. There is
no stopping to differentiate between the original geocentric
astronomers and their observations from the later heliocentric
astronomers who worked off the idea that the Earth moves between
Venus and Mars around the Sun so readers today don't concern
themselves with the level of knowledge of any given era as this will
be taken for granted in order to move the story along.

As the Earth moves through space in its circuit around the
Sun,certain stars lying on or near the same plane as the Earth's
orbital motion are temporarily lost behind the Sun's glare. The
older astronomers marked the passage as the Sun through the
constellations (hence birth signs) but for purposes of this story it
is better to consider the apparent motion of the stars behind the
Sun due to the orbital motion of the Earth -

https://www.youtube.com/watch?v=eeQwYrfmvoQ

The anchor for the Lat/Long system originally was based on the
appearance of one particular star as the orbital motion of the Earth
placed the star just far enough to one side of the Sun one morning,
That star was the brightest one in the celestial arena known as
Sirius and can be seen on the bottom left of the image -

https://www.youtube.com/watch?v=eeQwYrfmvoQ

".. on account of the procession of the rising of Sirius by one day
in the course of 4 years,.. therefore it shall be, that the year of
360 days and the 5 days added to their end, so one day shall be from
this day after every 4 years added to the 5 epagomenae before the
new year" Canopus Decree 238 BC

Unbeknownst to themselves, what the Egyptians were actually doing
was defining the Earth's orbital position around the Sun using the
seasonal appearance of a star as a gauge and the number of rotations
that fit inside an orbital circuit, in this case 1461 rotations for
4 orbital circuits which breaks down into 365 1/4 rotations to one
orbital circuit.

This is the founding principle where one 24 hour day keeps in step
with one rotation of the Earth and the basis of the Lat/Long system
along with the reason why the extra day and rotation is introduced
in order to keep the Earth's position in space fixed by the number
of rotations,at least to the nearest rotation.

The next step is the process which equates the 'average' 24 hour day
with 'constant' rotation insofar as the average 24 hour day
substitutes for constant rotation through 360 degrees in that period.






I am reacquainting myself with celestial mechanics as I am playing
with my new sextant.


I've thought about buying the Davis 25 plastic sextant to play with.
one practical use would be to confirm the height of the huge Linden
trees that border my back yard.
I did a google search and found a link that described how you could
estimate height with an upside down protractor, a string with a
weighted object as a kind of plumb bob and a ruler to sight along.The
ruler would sit on the upside down base of the protractor and the
string would give you the sighted angle. The guy provided the formula
to get a fairly accurate height.


You haven't mastered left, right, up, and down yet. You aren't ready for
a sextant yet.


In the cub scouts we learned to use a ruler held at arms length and a
bit of math to get the height of a tree or anything really.

On Thu, 8 Jan 2015 08:05:52 -0800 (PST), True North
wrote:

On Saturday, 3 January 2015 13:36:04 UTC-4, wrote:
On Sat, 3 Jan 2015 08:14:26 -0800 (PST),
wrote:

This is the broadest possible overview for those who are unfamiliar with how the motions of the Earth fit in with human timekeeping and although it is an injustice to those people who created the system we use today, the overview is much better than none at all. There is no stopping to differentiate between the original geocentric astronomers and their observations from the later heliocentric astronomers who worked off the idea that the Earth moves between Venus and Mars around the Sun so readers today don't concern themselves with the level of knowledge of any given era as this will be taken for granted in order to move the story along.

As the Earth moves through space in its circuit around the Sun,certain stars lying on or near the same plane as the Earth's orbital motion are temporarily lost behind the Sun's glare. The older astronomers marked the passage as the Sun through the constellations (hence birth signs) but for purposes of this story it is better to consider the apparent motion of the stars behind the Sun due to the orbital motion of the Earth -

https://www.youtube.com/watch?v=eeQwYrfmvoQ

The anchor for the Lat/Long system originally was based on the appearance of one particular star as the orbital motion of the Earth placed the star just far enough to one side of the Sun one morning, That star was the brightest one in the celestial arena known as Sirius and can be seen on the bottom left of the image -

https://www.youtube.com/watch?v=eeQwYrfmvoQ

".. on account of the procession of the rising of Sirius by one day in the course of 4 years,.. therefore it shall be, that the year of 360 days and the 5 days added to their end, so one day shall be from this day after every 4 years added to the 5 epagomenae before the new year" Canopus Decree 238 BC

Unbeknownst to themselves, what the Egyptians were actually doing was defining the Earth's orbital position around the Sun using the seasonal appearance of a star as a gauge and the number of rotations that fit inside an orbital circuit, in this case 1461 rotations for 4 orbital circuits which breaks down into 365 1/4 rotations to one orbital circuit.

This is the founding principle where one 24 hour day keeps in step with one rotation of the Earth and the basis of the Lat/Long system along with the reason why the extra day and rotation is introduced in order to keep the Earth's position in space fixed by the number of rotations,at least to the nearest rotation.

The next step is the process which equates the 'average' 24 hour day with 'constant' rotation insofar as the average 24 hour day substitutes for constant rotation through 360 degrees in that period.






I am reacquainting myself with celestial mechanics as I am playing
with my new sextant.


I've thought about buying the Davis 25 plastic sextant to play with. one practical use would be to confirm the height of the huge Linden trees that border my back yard.
I did a google search and found a link that described how you could estimate height with an upside down protractor, a string with a weighted object as a kind of plumb bob and a ruler to sight along.The ruler would sit on the upside down base of the protractor and the string would give you the sighted angle. The guy provided the formula to get a fairly accurate height.

Here, I just saved you a lot of money.

http://forestry.usu.edu/htm/kids-and...ht-measurement

On 1/8/2015 2:19 PM, wrote:
On Thu, 08 Jan 2015 12:24:14 -0500, KC wrote:

On 1/8/2015 12:13 PM, Justan Olphart wrote:
On 1/8/2015 11:05 AM, True North wrote:

I've thought about buying the Davis 25 plastic sextant to play with.
one practical use would be to confirm the height of the huge Linden
trees that border my back yard.
I did a google search and found a link that described how you could
estimate height with an upside down protractor, a string with a
weighted object as a kind of plumb bob and a ruler to sight along.The
ruler would sit on the upside down base of the protractor and the
string would give you the sighted angle. The guy provided the formula
to get a fairly accurate height.


You haven't mastered left, right, up, and down yet. You aren't ready for
a sextant yet.


In the cub scouts we learned to use a ruler held at arms length and a
bit of math to get the height of a tree or anything really.

There are a number of fairly simple geometry tricks to do things like
this. If you have the luxury of choosing your place to shoot the
angle, just use a regular 45 degree drafting triangle and a spirit
level.


Like I said, a 12 inch ruler or a plain old yard stick and your arm..
you need to know the length of your ruler from your eye, and the
distance to the *tree*.. No drafting triangle necessary at all

On 1/8/2015 8:48 PM, wrote:
On Thu, 08 Jan 2015 15:16:28 -0500, KC wrote:

On 1/8/2015 2:19 PM, wrote:
On Thu, 08 Jan 2015 12:24:14 -0500, KC wrote:

On 1/8/2015 12:13 PM, Justan Olphart wrote:
On 1/8/2015 11:05 AM, True North wrote:

I've thought about buying the Davis 25 plastic sextant to play with.
one practical use would be to confirm the height of the huge Linden
trees that border my back yard.
I did a google search and found a link that described how you could
estimate height with an upside down protractor, a string with a
weighted object as a kind of plumb bob and a ruler to sight along.The
ruler would sit on the upside down base of the protractor and the
string would give you the sighted angle. The guy provided the formula
to get a fairly accurate height.


You haven't mastered left, right, up, and down yet. You aren't ready for
a sextant yet.


In the cub scouts we learned to use a ruler held at arms length and a
bit of math to get the height of a tree or anything really.

There are a number of fairly simple geometry tricks to do things like
this. If you have the luxury of choosing your place to shoot the
angle, just use a regular 45 degree drafting triangle and a spirit
level.


Like I said, a 12 inch ruler or a plain old yard stick and your arm..
you need to know the length of your ruler from your eye, and the
distance to the *tree*.. No drafting triangle necessary at all

Just trying to remove the math for people who think trig is hard.


I forgot, we got lib arts students here...