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The First Known Interstellar Comet



 
 
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  #31  
Old November 1st 17, 07:37 AM posted to sci.astro.amateur
Gerald Kelleher
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Posts: 1,382
Default The First Known Interstellar Comet

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.

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  #32  
Old November 1st 17, 03:22 PM posted to sci.astro.amateur
Mike Collins[_4_]
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Posts: 2,789
Default The First Known Interstellar Comet

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. From the
Southern Hemisphere the stars appear upside down to those used to the
northern sky. So your left and right relative to the sun are reversed.
The reason I showed you the sky at dawn is to demonstrate this left /right
reversal. Just look at the positions of Jupiter, Mars and Venus.
If you keep on saying left and right you are being not just homocentric but
egocentric. And you will look like a fool for claiming something so
obviously wrong.


  #33  
Old November 1st 17, 05:14 PM posted to sci.astro.amateur
Gerald Kelleher
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Posts: 1,382
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.







  #34  
Old November 2nd 17, 12:17 AM posted to sci.astro.amateur
palsing[_2_]
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Posts: 2,749
Default The First Known Interstellar Comet

On Wednesday, November 1, 2017 at 9:14:25 AM UTC-7, Gerald Kelleher wrote:

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 -


Well, if you lived within 16 degrees of the north pole, Sirius won't rise at all for you, ever, so this claim of yours is an empty one!

If you live in a more reasonable location, Sirius will rise twice on one day each year... what do you suppose this indicates?

http://aa.usno.navy.mil/data/docs/mrst.php

Go to "Form B", for 'number of days' enter 365, for 'Celestial object of interest' scroll down to Sirius, for location enter 'Dublin' for example,
and hit 'compute data'. After the results are shown, scroll down to October 2nd, where you will find that, from Dublin, Sirius rose at 1 minute after midnight on Tuesday, October 2nd, and then rose again on the same day, October 2nd, at 3 minutes before midnight (and therefore just before October 3rd)... which, it seems, indicates that Sirius will rise 366 times each year. This fact, all by itself, should cause your head to explode!

There must be some logical explanation for this, right? Perhaps the US Naval Observatory is just making this up, or has made a horrible error of some kind... or maybe you are just uneducated enough not to know this, and are just too stubborn to even try to learn about sidereal time.

It is exactly like Neil deGrasse Tyson says...

http://weknowmemes.com/wp-content/up...ut-science.jpg

At some point in time, I hope you decide that astronomers are not as stupid as you seem to think they are, because the fact of the matter is they are as intelligent as people in any branch of science of your choosing, and the sooner you recognize this, the better.

Right now, you have no clue, you just don't know what you don't know.
  #35  
Old November 2nd 17, 09:20 AM posted to sci.astro.amateur
Gerald Kelleher
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Posts: 1,382
Default The First Known Interstellar Comet

On Wednesday, November 1, 2017 at 11:17:03 PM UTC, palsing wrote:
On Wednesday, November 1, 2017 at 9:14:25 AM UTC-7, Gerald Kelleher wrote:

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 -


Well, if you lived within 16 degrees of the north pole, Sirius won't rise at all for you, ever, so this claim of yours is an empty one!


You can have that one .




If you live in a more reasonable location, Sirius will rise twice on one day each year... what do you suppose this indicates?


Like Collins you can't extract yourself from daily rising/settings and reference the stars to the Stationary Sun. The new soft program will take into account that the orbital motion of the Earth causes the stars to transition from an evening appearance (left) to a morning appearance (right) so what the ancient astronomers were seeing when they saw Sirius rise with the Sun for the first time in weeks was actually a consequence of the orbital motion of the Earth -

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

When I talk about brief glimpse of the new software, this is what I mean as there is no daily rising and settings involved as the stellar transition of stars parallel to the orbital plane is as valid a proof for the Earth's orbital motion as direct/retrograde motions once were.





http://aa.usno.navy.mil/data/docs/mrst.php

Go to "Form B", for 'number of days' enter 365, for 'Celestial object of interest' scroll down to Sirius, for location enter 'Dublin' for example,
and hit 'compute data'. After the results are shown, scroll down to October 2nd, where you will find that, from Dublin, Sirius rose at 1 minute after midnight on Tuesday, October 2nd, and then rose again on the same day, October 2nd, at 3 minutes before midnight (and therefore just before October 3rd)... which, it seems, indicates that Sirius will rise 366 times each year. This fact, all by itself, should cause your head to explode!


I understand what you are trying to do as the Ra/Dec clockwork solar system is the only one you know. You can still keep it for your magnification hobby but what you cannot do is use it to model the motions of the Earth, solar system structure , extrapolate effects for terrestrial science from the motions of the Earth and many,many other things.






There must be some logical explanation for this, right? Perhaps the US Naval Observatory is just making this up, or has made a horrible error of some kind... or maybe you are just uneducated enough not to know this, and are just too stubborn to even try to learn about sidereal time.


Now, now Paul, this is not sci.physics.relativity where everyone eats one another as they dance to a tune that is anachronistic these days. The big organizations like NASA and the Naval Observatory are working with a timekeeping framework that renders observations into the familiar calendar format and this format by its very nature is a dating format for astronomical events that does not equate one year with one orbital circuit of the Sun as 3 years have 365 days/rotations in them and 1 year has 366 days/rotations in it.. The new software programs will effectively subtract any daily rotational components leaving researchers to model observations based on the orbital motion of the Earth alone in a Sun centered system. It will also free up the additional rotation which can be isolated through the Polar day/night cycle.









It is exactly like Neil deGrasse Tyson says...

http://weknowmemes.com/wp-content/up...ut-science.jpg

At some point in time, I hope you decide that astronomers are not as stupid as you seem to think they are, because the fact of the matter is they are as intelligent as people in any branch of science of your choosing, and the sooner you recognize this, the better.

Right now, you have no clue, you just don't know what you don't know.


You and everyone else here were brought up with the only show in town, in this case a rotating celestial sphere setup inherited from the late 17th century. I am easy with your desire to stay with this system even if it is meaningless for making sense of (even modelling) observations seen from a moving Earth or my own personal affection for terrestrial sciences and how the motions of the Earth influence them.

Fair dues to you, you state your case well and don't put words in my mouth and I can't ask for any more than that.

  #36  
Old November 2nd 17, 09:51 AM posted to sci.astro.amateur
Paul Schlyter[_3_]
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Posts: 1,266
Default The First Known Interstellar Comet

On Wed, 1 Nov 2017 14:22:37 -0000 (UTC), Mike Collins
wrote:


Left and right are subjective. From the


No, they are not. You cannot consider left to be right, or up, or
forward, just because you feel like doing so. Left and right are
objective, but they are in relation to one person's body. So left and
right are objective, and personal. Just like starboard and larboard
are objective and in relation to the body of not a person but a ship.
  #37  
Old November 2nd 17, 02:28 PM posted to sci.astro.amateur
Mike Collins[_4_]
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Posts: 2,789
Default The First Known Interstellar Comet

Paul Schlyter wrote:
On Wed, 1 Nov 2017 14:22:37 -0000 (UTC), Mike Collins
wrote:


Left and right are subjective. From the


No, they are not. You cannot consider left to be right, or up, or
forward, just because you feel like doing so. Left and right are
objective, but they are in relation to one person's body. So left and
right are objective, and personal. Just like starboard and larboard
are objective and in relation to the body of not a person but a ship.


Port and starboard are defined by the forward motion of a ship, otherwise
the red or green lights would have to be exchanged every time a vessel
changed from forward to reverse.
Left and right are much more vague. When two people are facing each other
you need to qualify to avoid ambiguity by saying “My left” or “Your left”.

The unremarkable clunky software Oriel is using to show the zodiacal motion
of the sun (I wrote better software than that in the 80s on a BBC micro) is
oriented with North at the top. If south were at the top the constellations
would move in the opposite directions.
Left and right are not precise enough to describe the motions of celestial
objects if you want to apply the description to the whole of the Earth. I
actually found it disconcerting in New Zealand to be walking in the
direction I knew was north while my instinct told me I was walking south.


  #38  
Old November 2nd 17, 02:53 PM posted to sci.astro.amateur
Gerald Kelleher
external usenet poster
 
Posts: 1,382
Default The First Known Interstellar Comet

On Thursday, November 2, 2017 at 1:28:10 PM UTC, Mike Collins wrote:


The unremarkable clunky software Oriel is using to show the zodiacal motion
of the sun


The software hasn't been developed yet to show the transition of celestial objects from an evening appearance to a morning appearance or from left to right of the stationary Sun. It subtracts all daily rotational components and all associated jargon of risings/settings with a simple perspective that allows proof of the Earth's orbital motion.

How do you know the Earth's orbits the Sun using the field of stars ?. The answer is found in the transition as the stars appear to move parallel to the orbital plane -

https://www.youtube.com/watch?v=eeQw...s&pbjreload=10


The Greeks had worked off the motion of the Sun through the Zodiac but the older system was the seasonal appearance of the stars and especially the brightest star out there. The original Sun centered astronomers inherited the Greek framework hence the difficulties with the direct/retrograde motions of Venus and Mercury that are easily accounted for by the older perspective relying on the seasonal appearance of the stars rather than the motion of the Sun.

Just as I thanked Paul Alsing for not putting words in my mouth, you descend to those fools who can't help themselves forcing my words into your own conceptions.




  #39  
Old November 2nd 17, 03:04 PM posted to sci.astro.amateur
Gerald Kelleher
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Posts: 1,382
Default The First Known Interstellar Comet

On Thursday, November 2, 2017 at 1:28:10 PM UTC, Mike Collins wrote:

Left and right are not precise enough to describe the motions of celestial
objects if you want to apply the description to the whole of the Earth. I
actually found it disconcerting in New Zealand to be walking in the
direction I knew was north while my instinct told me I was walking south.


Orbital comparisons made from Earth are contingent on what is moving from left to right or right to left with no ambiguities.

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

When Venus turns in behind the Sun seen from our slower moving Earth it moves from a morning appearance to an evening appearance.

When Venus reaches its widest point after it emerges as an evening appearance it will then turn back in front of the Sun and move from left to right until it overtakes us and becomes a morning appearance once more.

Overlaying the background stars into this picture to account for the Earth's orbital motion does not rely on the Sun moving right to left through the background stars but simply the Sun is stationary, the Earth is moving and the stars therefore transition from left to right of the central Sun as the Earth runs its circuit.

You once called yourself Mr Cool but I would say you are Mr Stone Cold in terms of inspiration and reasoning.

  #40  
Old November 2nd 17, 03:36 PM posted to sci.astro.amateur
Chris L Peterson
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Posts: 9,866
Default The First Known Interstellar Comet

On Thu, 2 Nov 2017 07:04:54 -0700 (PDT), Gerald Kelleher
wrote:

When Venus reaches its widest point after it emerges as an evening appearance it will then turn back in front of the Sun and move from left to right until it overtakes us and becomes a morning appearance once more.


What do "left" and "right" mean? If I walk outside today and look up
at the Sun while facing south, Venus will be on its left. If I'm
facing north, Venus will be on its right. It only makes sense to use
these terms when considering very specific viewpoints. In most cases,
they are ambiguous and non-useful. That's why we have astronomical
coordinate systems.
 




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