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Old November 1st 17, 04:14 PM posted to sci.astro.amateur
Gerald Kelleher
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Default The First Known Interstellar Comet

On Wednesday, November 1, 2017 at 2:22:39 PM UTC, Mike Collins wrote:
Gerald Kelleher wrote:
On Tuesday, October 31, 2017 at 10:54:12 PM UTC, Mike Collins wrote:
Gerald Kelleher wrote:
On Monday, October 30, 2017 at 9:48:32 AM UTC, Mike Collins wrote:
Gerald Kelleher wrote:
On Sunday, October 29, 2017 at 9:45:09 PM UTC, palsing wrote:
On Sunday, October 29, 2017 at 2:14:04 PM UTC-7, Gerald Kelleher wrote:

The chart and the software behind it is a celestial sphere contrivance
and totally unlike the new software which will present a
stationary/central Sun with everything moving left to right or right to
left depending on what celestial object is being considered. For my
part you are all welcome to your RA/Dec framework but it is a dead end
and utterly devoid of modelling uses even if it is great for predicting
events as dates within the calendar system.

You mean... you're NOT going to spend time on that web page and learn
something new? How sad...

A webpage where the Sun not only moves against the background stars but
also moves North and South against the same stars !!!!. Despite your
sadness, it may comes as no surprise that the new software program will
keep the Sun central and stationary thereby allow people to make sense of
the motions of faster moving planets (now a relative term). In some ways
they already do this but only in brief glimpses -

https://www.youtube.com/watch?v=MdFrE7hWj0A

Jupiter moves from an evening appearance to a morning appearance as the
faster motion of the Earth puts the planet from left to right of the
central Sun along with the background stars (in the case of the graphic,
ElNath, Castor and Pollucx ) however Jupiter will never pass in front of
the Sun as Venus and Mercury are seen to do. Not only will Venus and
Mercury show phase changes but also size increases/decreases as they
approach and recede from the Earth's wider orbital circumference and position.

Showing me manic descriptions of the Sun and planets against the
background stars contrasts with the graceful motions that comprise the
solar system structure so don't be sad for me.

You are so egocentric- in the sense of homocentric but even more. Left and
right? In the Southern Hemisphere it’s the other way round.

You haven't thought things through but then again when did you ever. In
the matter of Venus,the left of the Sun is an evening appearance in both
hemispheres and the right of the Sun is a morning appearance in both
hemispheres as judgments are made from the orbital motion of the Earth,
the orbital motion of Venus and the central Sun.

http://www.popastro.com/images/plane...ary%202012.jpg

The direction of the Earth's orbital motion is from left to right or
counter-clockwise as determined by the annual motion of the stars from
left to right of the Sun or alternatively from an evening to a morning appearance -

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


Don't bring a knife to a gunfight Collins. You are welcome to enjoy your
homocentric view with your two sticks, a watch and then concluding this
is a great way to link daily rotation directly to a whirling sphere of
stars but then you lose the ability to model solar system structure and
the relative perspectives seen from Earth or from the other planets. Try
it yourself, place two sticks in any direction and you will get the same
homocentric conclusion but what makes you crowd really, really dumb is
that once you recognize RA/Dec as a predictive convenience and not for
modelling then you can go your merry way. It is not just about being
right but the ability to enjoy astronomy and none of you seem to do that.
Maybe you are like the noisebox just looking for attention but I know you
can't promote your homocentric views in general or in detail while I now
couldn't care less.





In the Northern Hemisphere the Sun and planets appear to rise in the east
and move clockwise across the southern sky setting in the west. This is how
dawn looks in Great Yarmouth on November 1st 2017.



https://www.flickr.com/x/t/0090009/p...8/38021658066/


In the Southern Hemisphere the Sun and planets appear to rise in the east
and move anti-clockwise across the Northern sky setting in the West. This
is how dawn looks in Capetown on November 1st 2017.


https://www.flickr.com/x/t/0090009/p...8/38021655906/



The background stars move from an evening appearance to a dawn appearance
or from the left to the right of the Sun due solely to the orbital motion of the Earth.

Venus moves from an evening appearance to a morning appearance or from
left to right of the Sun as it approaches Earth at its closest point
regardless of where you live on the planet.

http://www.popastro.com/images/plane...ary%202012.jpg

You are still talking about planets rising and setting while I am
referencing their orbital motion to either the moving Earth or the
central and stationary Sun. The day you wake up and realize that the
magnificence of a stationary Sun comes into view due to a turning Earth
you may begin to appreciate what is being done here as you then turn you
attention and whatever curiosity you have left in you to the moving
planets and our orbital motion.

It is a different astronomical language and a different software program
is needed to express these principles.

Dawn has nothing to do with it. Left and right are subjective.


I wouldn't expect that you could accept a really old and venerable observation of a star that moves to the right of the Sun due solely to the orbital motion of the Earth. The ancient astronomers seen the star 'rise' with the Sun (dawn appearance) and known as a heliacal rising but in the Sun centered system it becomes the motion of the stars parallel to the orbital plane arising from the Earth's orbital motion -

https://www.youtube.com/watch?v=eeQwYrfmvoQ&t=14s

It doesn't matter where on the Earth you are, Sirius will go from an evening appearance to a morning appearance or from left to right of the central Sun just as the inner planets are seen to move from an evening appearance to a dawn appearance due to their faster orbital motion -

http://www.popastro.com/images/plane...ary%202012.jpg

The Greeks used the less productive motion of the Sun through the constellations but even here the motion of the stars from the left to right of the central Sun can be swapped from the motion of the Sun from right to left of the stars. In a Sun centered system the former perception dictates all other motions referenced to the Sun including the faster moving planets Venus and Mercury.

Let's face it, a redneck is not going to change his ways to something productive where the references for orbital motion between planets don't require people to thing in terms of upside down as all inhabitants on Earth look out at the Sun and the motions of the planets to the Earth,to each other and to the central Sun. Nothing subjective about it, neither the transition from evening to morning or from left to right of the central Sun reference.