Precession of the equinoxes??

I have a couple of questions that you lot will probably find a bit naive -

Question 1

The precession of the Equinoxes causes the Earth's axis to describe a
circle in the sky and takes 25,800 years to complete. As the precession
progresses the tilt of the Earth's axis changes and the seasons should
advance/retard with respect to the beginning of the calendar year. This
should mean that in half that time, ie 12,900 years the northern hemisphere
winter will be in July/August and not January/February. The same should
have occurred 12,900 years ago. Am I correct in thinking this? If not,
why not? Does this have anything to do with Ice Ages? (A couple of extra
questions :] ).

Question 2

Recorded history covers about the last 5000 years - this is about 1/5 of
the precession cycle. The seasons should have advanced/retarded about 1/5
of a year during this time - ie about 2.4 months. Is there any evidence
in recorded history to show whether Summer or Winter has occured at a
different time of the year to what it does now?

Alan

Alan Brown wrote in message ...
I have a couple of questions that you lot will probably find a bit naive -

Question 1

The precession of the Equinoxes causes the Earth's axis to describe a
circle in the sky and takes 25,800 years to complete. As the precession
progresses the tilt of the Earth's axis changes and the seasons should
advance/retard with respect to the beginning of the calendar year. This
should mean that in half that time, ie 12,900 years the northern hemisphere
winter will be in July/August and not January/February. The same should
have occurred 12,900 years ago. Am I correct in thinking this? If not,
why not? Does this have anything to do with Ice Ages? (A couple of extra
questions :] ).


We determine the year based on the Sun and its relationship to the
Earth's tilt. Therefore the Spring Equinox, the day the Sun appears
to cross the equator as it's northward bound, determines the first day
of spring. The calendar has been set up to stay in synch with
equinoxes and the solstices, therefore you will never have winter in
July/August in the northern hemisphere. However what you do see is
the Vernal Equinox slowly progressing through the constellations as
the millennia go by. It is currently moving into Aquarius. This is
why the "Age of Aquarius" and all that. If on the other hand we were
to go by the stars to determine the year (sidereal year), then we
would see the seasons slipping.

There may be some connection between the precession of the poles and
ice ages. When the axis is aligned so that summer comes to the
northern hemisphere while the Earth is at the Aphelion of its orbit
(farthest from the Sun), then the summers will be cooler, but the
winters will be milder. But when summer comes when the Earth is at
its parihelion, then the summers will be hotter and the winters will
be colder.


Question 2

Recorded history covers about the last 5000 years - this is about 1/5 of
the precession cycle. The seasons should have advanced/retarded about 1/5
of a year during this time - ie about 2.4 months. Is there any evidence
in recorded history to show whether Summer or Winter has occured at a
different time of the year to what it does now?

Alan


The only thing like this was caused by the old Julian calendar being a
little out of synch with the solar year. That's why they adopted the
Gregorian calendar a couple hundred years ago, which includes the leap
year days to keep it in synch.

Double-A

Alan Brown wrote in message ...
I have a couple of questions that you lot will probably find a bit naive -

Question 1

The precession of the Equinoxes causes the Earth's axis to describe a
circle in the sky and takes 25,800 years to complete. As the precession
progresses the tilt of the Earth's axis changes and the seasons should
advance/retard with respect to the beginning of the calendar year. This
should mean that in half that time, ie 12,900 years the northern hemisphere
winter will be in July/August and not January/February. The same should
have occurred 12,900 years ago. Am I correct in thinking this? If not,
why not? Does this have anything to do with Ice Ages? (A couple of extra
questions :] ).


We determine the year based on the Sun and its relationship to the
Earth's tilt. Therefore the Spring Equinox, the day the Sun appears
to cross the equator as it's northward bound, determines the first day
of spring. The calendar has been set up to stay in synch with
equinoxes and the solstices, therefore you will never have winter in
July/August in the northern hemisphere. However what you do see is
the Vernal Equinox slowly progressing through the constellations as
the millennia go by. It is currently moving into Aquarius. This is
why the "Age of Aquarius" and all that. If on the other hand we were
to go by the stars to determine the year (sidereal year), then we
would see the seasons slipping.

There may be some connection between the precession of the poles and
ice ages. When the axis is aligned so that summer comes to the
northern hemisphere while the Earth is at the Aphelion of its orbit
(farthest from the Sun), then the summers will be cooler, but the
winters will be milder. But when summer comes when the Earth is at
its parihelion, then the summers will be hotter and the winters will
be colder.


Question 2

Recorded history covers about the last 5000 years - this is about 1/5 of
the precession cycle. The seasons should have advanced/retarded about 1/5
of a year during this time - ie about 2.4 months. Is there any evidence
in recorded history to show whether Summer or Winter has occured at a
different time of the year to what it does now?

Alan


The only thing like this was caused by the old Julian calendar being a
little out of synch with the solar year. That's why they adopted the
Gregorian calendar a couple hundred years ago, which includes the leap
year days to keep it in synch.

Double-A

(Double-A) wrote in
om:

Alan Brown wrote in message
...
I have a couple of questions that you lot will probably find a bit
naive -

Question 1

The precession of the Equinoxes causes the Earth's axis to describe a
circle in the sky and takes 25,800 years to complete. As the
precession progresses the tilt of the Earth's axis changes and the
seasons should advance/retard with respect to the beginning of the
calendar year. This should mean that in half that time, ie 12,900
years the northern hemisphere winter will be in July/August and not
January/February. The same should have occurred 12,900 years ago.
Am I correct in thinking this? If not, why not? Does this have
anything to do with Ice Ages? (A couple of extra questions :] ).


We determine the year based on the Sun and its relationship to the
Earth's tilt. Therefore the Spring Equinox, the day the Sun appears
to cross the equator as it's northward bound, determines the first day
of spring. The calendar has been set up to stay in synch with
equinoxes and the solstices, therefore you will never have winter in
July/August in the northern hemisphere. However what you do see is
the Vernal Equinox slowly progressing through the constellations as
the millennia go by. It is currently moving into Aquarius. This is
why the "Age of Aquarius" and all that. If on the other hand we were
to go by the stars to determine the year (sidereal year), then we
would see the seasons slipping.

There may be some connection between the precession of the poles and
ice ages. When the axis is aligned so that summer comes to the
northern hemisphere while the Earth is at the Aphelion of its orbit
(farthest from the Sun), then the summers will be cooler, but the
winters will be milder. But when summer comes when the Earth is at
its parihelion, then the summers will be hotter and the winters will
be colder.


Question 2

Recorded history covers about the last 5000 years - this is about 1/5
of the precession cycle. The seasons should have advanced/retarded
about 1/5 of a year during this time - ie about 2.4 months. Is
there any evidence in recorded history to show whether Summer or
Winter has occured at a different time of the year to what it does
now?

Alan


The only thing like this was caused by the old Julian calendar being a
little out of synch with the solar year. That's why they adopted the
Gregorian calendar a couple hundred years ago, which includes the leap
year days to keep it in synch.

Double-A


Thanks for your reply. I have followed what you said. I dont know a lot
about astronomy but I find it fascinating.

Thanks again

Alan

(Double-A) wrote in
om:

Alan Brown wrote in message
...
I have a couple of questions that you lot will probably find a bit
naive -

Question 1

The precession of the Equinoxes causes the Earth's axis to describe a
circle in the sky and takes 25,800 years to complete. As the
precession progresses the tilt of the Earth's axis changes and the
seasons should advance/retard with respect to the beginning of the
calendar year. This should mean that in half that time, ie 12,900
years the northern hemisphere winter will be in July/August and not
January/February. The same should have occurred 12,900 years ago.
Am I correct in thinking this? If not, why not? Does this have
anything to do with Ice Ages? (A couple of extra questions :] ).


We determine the year based on the Sun and its relationship to the
Earth's tilt. Therefore the Spring Equinox, the day the Sun appears
to cross the equator as it's northward bound, determines the first day
of spring. The calendar has been set up to stay in synch with
equinoxes and the solstices, therefore you will never have winter in
July/August in the northern hemisphere. However what you do see is
the Vernal Equinox slowly progressing through the constellations as
the millennia go by. It is currently moving into Aquarius. This is
why the "Age of Aquarius" and all that. If on the other hand we were
to go by the stars to determine the year (sidereal year), then we
would see the seasons slipping.

There may be some connection between the precession of the poles and
ice ages. When the axis is aligned so that summer comes to the
northern hemisphere while the Earth is at the Aphelion of its orbit
(farthest from the Sun), then the summers will be cooler, but the
winters will be milder. But when summer comes when the Earth is at
its parihelion, then the summers will be hotter and the winters will
be colder.


Question 2

Recorded history covers about the last 5000 years - this is about 1/5
of the precession cycle. The seasons should have advanced/retarded
about 1/5 of a year during this time - ie about 2.4 months. Is
there any evidence in recorded history to show whether Summer or
Winter has occured at a different time of the year to what it does
now?

Alan


The only thing like this was caused by the old Julian calendar being a
little out of synch with the solar year. That's why they adopted the
Gregorian calendar a couple hundred years ago, which includes the leap
year days to keep it in synch.

Double-A


Thanks for your reply. I have followed what you said. I dont know a lot
about astronomy but I find it fascinating.

Thanks again

Alan