Astronomy software

Hello all,

I wonder if there are software that would calculate the rate of precession as you move through time, forward and backward. For instance, in about 12 000 years, Vega will be the north star. Are there software that would determine accurately the movements of all stars.

Thanks

Andre

On Fri, 10 Apr 2015 14:56:56 -0700 (PDT), Andre
wrote:

I wonder if there are software that would calculate the rate of precession as you move through time, forward and backward. For instance, in about 12 000 years, Vega will be the north star. Are there software that would determine accurately the movements of all stars.

Essentially all planetarium apps calculate precession and use it for
plotting the sky in the past and future. Keep in mind that the values
used for long time scales are approximations, and not very good ones.
Accurate calculations of precession beyond a couple thousand years in
either direction don't exist.

On Fri, 10 Apr 2015 17:12:44 -0600, Chris L Peterson
wrote this crap:


Essentially all planetarium apps calculate precession and use it for
plotting the sky in the past and future. Keep in mind that the values
used for long time scales are approximations, and not very good ones.
Accurate calculations of precession beyond a couple thousand years in
either direction don't exist.

I don't believe you. At the university I went to school at, I was
very familiar with the planetarium. The stars were projected on the
ceiling dome with a globe which had lights attached. The lights were
fixed which could not have provided precession.

Perhaps there are newer types which allow for precession, but I
haven't been into a planetarium in 35 years.


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On Fri, 10 Apr 2015 23:18:37 -0400, Lord Vath
wrote:

On Fri, 10 Apr 2015 17:12:44 -0600, Chris L Peterson
wrote this crap:


Essentially all planetarium apps calculate precession and use it for
plotting the sky in the past and future. Keep in mind that the values
used for long time scales are approximations, and not very good ones.
Accurate calculations of precession beyond a couple thousand years in
either direction don't exist.

I don't believe you. At the university I went to school at, I was
very familiar with the planetarium. The stars were projected on the
ceiling dome with a globe which had lights attached. The lights were
fixed which could not have provided precession.

I'm not sure why you're discussing planetariums. The discussion is
about planetarium software.

That said, precession doesn't change the pattern of the stars, only
their position with respect to the Earth's poles. Plenty of old-style
star ball planetariums could demonstrate precession.

Perhaps there are newer types which allow for precession, but I
haven't been into a planetarium in 35 years.

Most planetarium projectors these days are digital, and can project
any image. These are controlled by planetarium software similar to the
programs we're discussing here, so in addition to precession, they can
also correct for stellar proper motion, and therefore show how well
known constellations have changed their shapes in the past, and will
do so in the future.

On Fri, 10 Apr 2015 17:12:44 -0600, Chris L Peterson
wrote:
Accurate calculations of precession beyond a couple thousand years
in
either direction don't exist.

? don't think he wanted the same accuracy level as the position today
and in the near future and past. There are planispheres that show the
precession many thousands of years into the past and the future btw,
but their approximation is to ignore variations in the inclination of
the axis of the Earth.

On Fri, 10 Apr 2015 14:56:56 -0700 (PDT), Andre
wrote this crap:

Hello all,

I wonder if there are software that would calculate the rate
of precession as you move through time, forward and backward.
For instance, in about 12 000 years, Vega will be the north star.
Are there software that would determine accurately the movements of all stars.

Thanks

Andre

Good question. I tried Redshift but the maximum date I could set it
to was 11000AD. And the constellations were the same, and Polaris was
in the same place.

I'm sure there are some programs because I've seen predictions of
where the stars will be and how the constellations will look. But
they might not be commercially available.


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On 11/04/2015 00:20, Lord Vath wrote:
On Fri, 10 Apr 2015 14:56:56 -0700 (PDT), Andre
wrote this crap:

Hello all,

I wonder if there are software that would calculate the rate
of precession as you move through time, forward and backward.

Almost all of them. How far they will let you take it is another matter
but most should allow +/- 10000y (some allow more than others).

For instance, in about 12 000 years, Vega will be the north star.
Are there software that would determine accurately the movements of all stars.

Try Stellarium. That will let you see the sky over a precession cycle
and put an equatorial grid on so you can see where the pole is.

Advancing the year will allow you to see Polaris moving relative to the
grid (it will be a more accurate pole star for couple of hundred years).

Thanks

Andre

Good question. I tried Redshift but the maximum date I could set it
to was 11000AD. And the constellations were the same, and Polaris was
in the same place.

It isn't Polaris that moves! It is the axis of rotation of the Earth
that precesses away from Polaris (which is a chance alignment today).

The constellations will look the same unless you go millions of years
into the future when a handful of stars may have exploded, been born or
have sufficiently large proper motions to matter.

I'm sure there are some programs because I've seen predictions of
where the stars will be and how the constellations will look. But
they might not be commercially available.

Even the humble Stellarium will do this and all serious astronomy
charting programs will since handling precession to epoch of date is
essential for any system that wants to point a telescope at an object.

In the bad old days star charts were redrawn every 50 years and showed
their specific epoch on the front cover.


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However, its owner is clueless about astronomy.

--
Regards,
Martin Brown

On Saturday, April 11, 2015 at 8:49:59 AM UTC+1, Martin Brown wrote:


It isn't Polaris that moves! It is the axis of rotation of the Earth
that precesses away from Polaris (which is a chance alignment today).



I love the new freedom of operating in SAA.

http://www.english-heritage.org.uk/v...tory/building/

This magnificent structure makes rubbish of your weak approach to the precession of the Equinoxes as the orientation of the Earth to the Summer and Winter Solstices must remain the same today as 2500 years ago to permit the continuing alignments to the orbital points , likewise the older Newgrange and Knowth monuments.

'Axial precession' is from the same framework that causes Sirius to drift back into the Sun's glare by virtue of the proportion of rotations to orbital circuits and the apparent motion of the stars in sequence behind the Sun. It is a more refined adjustment than the leap day correction and that is it.

On Sat, 11 Apr 2015 08:49:47 +0100, Martin Brown
wrote this crap:

On 11/04/2015 00:20, Lord Vath wrote:
On Fri, 10 Apr 2015 14:56:56 -0700 (PDT), Andre
wrote this crap:

This signature is now the ultimate
power in the universe

However, its owner is clueless about astronomy.

I took 400 level astronomy classes at the university. I doubt you
ever finished high school.


This signature is now the ultimate
power in the universe

Andre wrote:
Hello all,

I wonder if there are software that would calculate the rate of
precession as you move through time, forward and backward. For instance,
in about 12 000 years, Vega will be the north star. Are there software
that would determine accurately the movements of all stars.

Thanks

Andre

Slellarium is supposed to be OK for 100,000 years for precession but I
don't know about proper motion. It's free for PC and very cheap for phones
and tablets so why not just try it. There are reports on the net of
accurate depiction of Orion at the time the pyramids were built.