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Main
Date: 27 Aug 2007 12:00:27
From: oriel36
Subject: Using transits properly
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As the Earth overtakes Jupiter in our respective orbit around the
Sun,the shadow cast by Io will alter its position as we approach
Jupiter and leave it behind insofar as our orbital motion is faster.
Guess which images indicates our approach to Jupiter and which one
represents leaving it behind via the shadow orientation ? -
http://eeyore.astro.uiuc.edu/~lwl/classes/astro100/fall03/Images/jupiotrans.jpg
http://antwrp.gsfc.nasa.gov/apod/image/9904/ioshadowc_hst_big.jpg
There are planetary transits and then there are those of satellites
such Io,great ways to use them other than describe them for the
purpose of explaining the solar system cycles.I will be the first to
congratulate a person for coming up with novel ideas to use images and
time lapse footage such as Mr Tezel who first showed Copernican
reasoning using contemporary technoilogy -
http://antwrp.gsfc.nasa.gov/apod/image/0112/JuSa2000_tezel.gif
You want this forum to thrive or not ?.
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Date: 30 Aug 2007 11:07:19
From: oriel36
Subject: Re: Using transits properly
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On Aug 30, 6:37 pm, Margo Schulter <mschul...@web1.calweb.com > wrote:
> oriel36 <geraldkelle...@yahoo.com> wrote:
> > Your astrological Ra/Dec system tries to turn the stable principles
> > on its head by trying to gauge axial rotation directly by using the
> > return of a star to a meridian .It means that you cannot explain or
> > understand where the 24 hour cycle comes from,how it elapses
> > seamlessly from cycle to the next and ultimately into the wider
> > practicalities of clocks and how they are used for civil purposes.
>
> Please let me thank you for taking the time to engage in friendly
> dialogue, as also with another article to which I've just responded.
> As I see it, RA/Dec is merely a convenient system, and in fact
> illustrates how the sidereal day is about 4 minutes shorter than
> 24 hours.
>
> > The Ra/Dec framework is only an observational convenience,it is
> > totally astrologicval in content and character and I assure you it is
> > not and never will be a working principle for astronomy.
>
> Well, I see it as _precisely_ "an observational convenience."
>
Unfortunately it is the basis for physically representing axial and
orbital motion -
http://en.wikipedia.org/wiki/Image:Tiempo_sid%C3%A9reo.en.png
I have explained in detail that a star returning constantly in 23
hours 56 minutes requires the calendar system to work and subsequently
that system based on 3 years of 365 days and 1 year of 366 days is
unsuitable for justifying axial and orbital motion.
I certainly believe that there are enough intelligent people here who
are familiar with the topic to create the background situation to
deal with the matter and especially with textual support from the
astronomical treatise by Huygens -
http://www.xs4all.nl/~adcs/Huygens/06/kort-E.html
I will say nothing of what it feels like since I found the Huygens
text which shows how and why clocks are kept in sync with the axial
cycle as opposed to the false assumptions made by Flamsteed based on
using clocks to determine axial rotation directly,again,these things
have to be dealt with before any stability returns to astronomy.If you
think the feeling was relief at finding the text I assure you it was
and remains otherwise.
You enter the forum at a very unique juncture ,many here will tell you
that, but what the participants want s.a.a to become remains to be
seen.For my part,astronomy is as much a discipline of the day than it
is of the night,it speaks the language of geology and climatology in
the great and small cycles and my lament has been that if people
cannot appreciate the most fundamental daily one,appreciation of
everything else suffers.You want to be drawn down to the page and
equations ect but astronomy is mostly about giving clearer details to
what most already know,in short, it is just as much about the heart
than the head.
I read on but you never get past the 'sidereal day' and treat it as a
factual thing and from that point of departure astronomy,its methods
and insights wither.
Take care now.
> > It was Flamsteed who make that awful mistake of tying axial rotation
> > directly to the return of a star in 23 hours 56 minutes 04 seconds -
>
> > "... our clocks kept so good a correspondence with the Heavens that I
> > doubt it not but they would prove the revolutions of the Earth to be
> > isochronical..." Flamsteed
>
> > You really have no idea just how shocking that statement is do you ?.
>
> Maybe learning a bit about the history of science has made me hard
> to "shock." While Thomas Kuhn's view of scientific developments
> involving the creation, "normal" research within, and change of
> paradigms is controversial, I would say it nicely illustrates how
> worldviews do change. Also, just as in certain legal systems there
> is a principle of _stare decisis_ or "standing by things decided"
> unless/until there is compelling reason to alter them, so in science
> as analyzed by Kuhn, there is a tendency to "stand by" established
> paradigms until the anomalies clearly justify a consensus that
> recognizing a "revolution" or paradigm change is in order.
>
> Thus I know that Galileo, in a famous debate about the comets of 1618
> with Father Horatio (or Orazio) Grassi, took what we now know is the
> wrong side of the argument, asserting that comets were mere
> meteorological phenomena rather than celestial objects from beyond
> the Moon's orbit. More regrettably, Galileo had considerable literary
> fun at Grassi's expense (astronomical disputations then, as on Usenet
> today, sometimes skirting the territory of what might be called
> personal abuse). Should I be "shocked"? -- or merely learn that
> scientists are fallible.
>
> The "untidiness" of the material, from a certain point of view, can
> arise in various disciplines -- for example, music, where 12 pure
> fifths at a ratio of 3:2 slightly exceed 7 pure octaves at 2:1, the
> famous Pythagorean comma (maybe a bit like the difference between
> the sidereal day and 24 hours). These differences may be ignored,
> catered for, or "tempered out" in various ways.
>
> Should I be shocked that in 1618, the year of those brilliant
> comets and also a rich decade for Kepler, an Italian musician
> and theorist named Fabio Colonna published a fascinating book
> on his harpsichord with 31 notes per octave in which he asserted
> that using a standard tuning (likely based on four slightly
> narrow fifths yielding a pure major third at 5:4), the octave
> would be divided into 31 equal parts -- when we now know that
> those parts would in fact be slightly unequal?
>
> To me, these small anomalies, commas, or "untidinesses" as we
> might see it from a certain point of view aren't shocking, nor
> the fact that scientists and musicians don't always write precisely,
> or have the necessary tools and information to do so as we would
> now judge the "precise" situation.
>
> > I am almost certain that there are a few people here who are capable
> > of disengaging the calendrically based observational convenience of
> > the Ra/Dec system from heliocentric reasoning insofar as the
> > reasoning which led Flamsteed to his muddleheaded conclusion for axial
> > rotation requires a nonsensical observation that the natural noon
> > cycle is 24 hours exactly -
>
> >http://en.wikipedia.org/wiki/Image:Tiempo_sid%C3%A9reo.en.png
>
> > Astronomically,that graphic is more shocking than believing in a flat
> > or stationary Earth but apparently you are prepared to beleive it.
>
> Certainly I know that the sidereal day is about four minutes shorter
> than 24 hours -- as the changes in the sky outside my observatory
> show quite pragmatically. I also assure you that I regard the Sun
> as the focus of the planetary orbits. As far as I know, Newton,
> Flamsteed, etc., sought to follow a Copernican and Keplerian
> outlook, whatever their imprecisions or infelicities as you
> view them.
>
> Then, again, in 1814 if I recall the date of the article correctly,
> William Herschel attempted to sum up his experience of observing
> and classifying 2500 or so nebulae with state-of-the-art techniques
> (and he had what would now be called here a case of "aperture fever,"
> craving for bigger and better telescopes and pushing the envelope
> as well as his allotted budgets to build them) by positing an
> evolutionary theory of these objects. Unfortunately, as we now
> recognize, he regarded what we classify as open and globular
> star clusters as well as galaxies as objects of the same order,
> and thus possibly as all "life history" stages that might be
> exhibited by a given system.
>
> Today we would say that he was absolutely right in taking an
> evolutionary approach, as in the preface to one of his catalogs
> (1789, his second catalogue of 1000 nebulae), where he compares
> the universe to a "luxuriant garden" where, by observing plants
> at different stages of growth, we can, in effect, extend our
> time perception.
>
> However, since galaxies and their components such as open or
> globular clusters weren't yet recognized as in distinct
> categories, his attempt to propose a specific sequence of
> evolution proved less than accurate. Indeed, it was only
> with Leavitt's discovery of the Cepheid "standard candle"
> and the application of this to the Cepheids of M31, for
> example, that the nature of our own galactic Local Group
> was revealed (see the famous Shapley-Curtis debate as
> late as 1920 or so, just before this clarification).
> If Herschel had had this information available in 1814,
> then obviously his evolutionary scheme would have been
> different, and possibly more accurate as we now judge it.
>
> >> Are you saying that RA and Dec aren't the best system for
> >> celestial coordinates -- and, if so, how can we do it better?
>
> > I have no problem with the observational convenience of the Ra/Dec
> > system,.none whatsoever,just so long as it is not used to express the
> > axial and orbital motions of the Earth.The dominant concept for axial
> > and orbital motion believes that it does -
>
> >http://hypertextbook.com/facts/1999/JennyChen.shtml
>
> Maybe I'm not getting this, but I read this source as saying
> that a sidereal day is shorter than 24 hours by about 4 minutes,
> which sounds accurate enough. Is there a disagreement here about
> any relevant facts, or just about the most felicitous way to
> state them?
>
> > The use of constellational geometry to determine objects is fine if
> > all you are doing is magnifying objects.It is not fine for structural
> > astronomy such as heliocentric reasoning.
>
> As I see it, constellational geometry is fine for naked eye as well
> optically aided observation, or pointing a device registering other
> electromagnetic wavelengths also.
>
> > Your concerns do not rise much above magnification whereas I have
> > tried to show just how sprawling astronomy actually is,not just
> > structurally and in terms of the timekeeping systems but historically
> > as well.I have looked at the fiction surrounding astronomical
> > discoveries and how they have been directed towards empirical
> > agendas,to all intents and purposes Newton takes the role of
> > inheriting the works of Copernicus,Kepler and Roemer when the guy
> > basically ransacked their discoveries to suit his careless agenda..
>
> Please let me clarify first, that as I see it, an astronomer's business
> may be summed up in the fine phrase "minding the heavens" -- and seeking
> to understand their "construction" and dynamics.
>
> Maybe I should clarify a small point: even in narrow technical terms,
> the purpose of a telescope is not merely to "magnify," but to gather
> more light than the unaided human eye can collect from remote objects.
> Thus William Herschel speaks of "the power of penetrating space" which
> telescopes have in proportion to this light-gathering ability.
>
> Indeed it is a commonplace on s.a.a. and elsewhere that a newcomer
> to observational astronomy may often be under the impression that
> a telescope is rated by its "power," a misconception promoted by
> advertisements for certain telescopes claiming very high
> magnifications such as "675X." In fact, aperture is the better
> index of "penetrating power," as William Herschel very lucidly
> and engagingly explains in an article on this subject. It is
> quite possible to use a telescope at magnifications where the
> light-gathering power is inadequate to resolve detail adequately;
> which is why advertisements for small refractors at "675X" or the
> like may be literally accurately, but practically very misleading.
>
> Thus I would say that the concern of an astronomer is not mere
> "magnification," but rather resolution -- to shed more light on
> an object or celestial system, often optically but above all
> intellectually.
>
> With the greatest admiration for Roemer (who made the first
> astronomical estimation of the speed of light in 1676) and
> his predecessors and contemporaries such as Huygens (a great
> figure in astronomy and the theory of musical intonation
> alike), I would say that if we consider "just how sprawling
> astronomy actually is," then Newton's encompassing agenda
> can hardly be described as "careless."
>
> Einstein, whose Special and General Relativity can be seen
> at once as superceding and consummately ...
>
> read more =BB
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Date: 29 Aug 2007 04:35:54
From: oriel36
Subject: Re: Using transits properly
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On Aug 28, 10:54 pm, br...@isi.edu wrote:
> Margo Schulter wrote (in response to oriel36/Gerald Kelleher):
>
> > Hi, there, and I certainly do want s.a.a. to thrive, and
> > serve as a place where people can learn, share, and refine
> > the best observing techniques. This is where I am coming
> > from in offering the following comment.
>
> Margo, Oriel/Gerald Kelleher is a write-only poster. It is next
> to pointless to convince him to participate constructively on
> SAA.
>
> >From MOPFAQ (link below):
>
> Q. What is the deal with [insert nut]?
>
> A. [snip]
>
> Gerald Kelleher (aka oriel36) is a celestial mechanics nut who thinks
> that astronomy should have stopped with Kepler, and never gone on to
> the
> analytical universe of forces and accelerations put forth by Newton.
You may not be an astronomer enough to spot where Isaac jumped the
tracks in respect to his approach and resolution of retrogrades,the
main Copernican argument for using the orbital motion of the Earth
around the Sun to resolve the observed behavior of the other
planets .Advances in imaging and especially time lapse footage of
Jupiter and Saturn being actuall;y overtaken by an orbitally moving
Earth make the whole thing enjoyable -
http://antwrp.gsfc.nasa.gov/apod/image/0112/JuSa2000_tezel.gif
Nobody should have an objection to the simple statement that against
the stellar background the planets appear to move forwards,backwards
and then forwards agains but from an orbitally moving Earth the
planets,including ours,move in a forward direction around the central
Sun.
Poor Isaac got it wrong by creating a hypothetical observer on the
Sun to resolve what can only be resolved from an observer orbitally
moving Earth-
"For to the earth planetary motions appear sometimes direct,
sometimes stationary, nay, and sometimes retrograde. But from the sun
they are always seen direct, " Newton
So,it is something else to promote the incredible technological
achievements in imaging to promote Copernican heliocentric reasoning
to a crowd intent on promoting a false view of retrogrades and their
resolution via Newton.
Don't forget Brian that the resolution for the observed behavior of
the other planets using the orbital motion of the Earth then allowed
Copernicus to infer axial rotation as the cause of the daily
cycle,from there we get the 24 hour/360 degree correlation linking
clocks with terrestrial longitudes.
> He
> seems quite taken with the elegance and beauty of the music of the
> ellipses that Kepler recorded. Whenever a thread on celestial
> mechanics
> (or indeed anything having to do with celestial motions) comes up, he
> can be counted on to throw in his two cents worth, usually denigrating
> any competent contributor who's moved beyond the 17th century. He
> wastes no time reading any rebuttals to his posts, so there's no point
> wasting any time writing them. He also starts a few threads of his
> own,
> whenever it seems that interest in 16th-century celestial mechanics
> might be flagging.
>
> *****
>
> I'm sure Gerald will take offense. Sorry about that.
>
> --
> Brian Tung <br...@isi.edu >
> The Astronomy Corner athttp://astro.isi.edu/
> Unofficial C5+ Home Page athttp://astro.isi.edu/c5plus/
> The PleiadAtlas Home Page athttp://astro.isi.edu/pleiadatlas/
> My Own Personal FAQ (SAA) athttp://astro.isi.edu/reference/faq.html
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Date: 29 Aug 2007 04:20:23
From: oriel36
Subject: Re: Using transits properly
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On Aug 28, 9:50 pm, Margo Schulter <mschul...@web1.calweb.com > wrote:
> oriel36 <geraldkelle...@yahoo.com> wrote:
>
> > You want this forum to thrive or not ?.
>
> Hi, there, and I certainly do want s.a.a. to thrive, and
> serve as a place where people can learn, share, and refine
> the best observing techniques. This is where I am coming
> from in offering the following comment.
>
> For some time I have been reading your posts, which seem to
> strive for some kind of new or alternative paradigm for
> mapping the celestial sphere and timekeeping.
You are mistaken,the stable principles of astronomical timekeeping
involve a precise method for determining the 24 hour day,how that
human devised cycle is kept in sync with the natural noon cycles and
ultimately how clocks determine distance by virtue of the 4 minute for
1 degree of geographical seperation.
Your astrological Ra/Dec system tries to turn the stable principles
on its head by trying to gauge axial rotation directly by using the
return of a star to a meridian .It means that you cannot explain or
understand where the 24 hour cycle comes from,how it elapses
seamlessly from cycle to the next and ultimately into the wider
practicalities of clocks and how they are used for civil purposes.
To the degree
> that this effects practical observing techniques, like how
> one specifies and locates the coordinates for a given object
> of interest (say M31), it _is_ relevant to the specific
> charter of s.a.a.
>
The Ra/Dec framework is only an observational convenience,it is
totally astrologicval in content and character and I assure you it is
not and never will be a working principle for astronomy.
> While many of your posts seem to decry the methods of certain
> noted astronomers, including John Flamsteed, who along with
> his wife and assistant Margaret Flamsteed (for whom my 20cm
> Dob is named) compiled a great star catalogue, and also
> unknowingly discovered the Georgian planet (also known as
> Uranus) as "34 Tauri" in 1690, the question that I and
> possibly others here might ask is: "What is your alternative?
> Show us how it would work for our night-to-night observing."
>
It was Flamsteed who make that awful mistake of tying axial rotation
directly to the return of a star in 23 hours 56 minutes 04 seconds -
"... our clocks kept so good a correspondence with the Heavens that I
doubt it not but they would prove the revolutions of the Earth to be
isochronical..." Flamsteed
You really have no idea just how shocking that statement is do you ?.
I am almost certain that there are a few people here who are capable
of disengaging the calendrically based observational convenience of
the Ra/Dec system from heliocentric reasoning insofar as the
reasoning which led Flamsteed to his muddleheaded conclusion for axial
rotation requires a nonsensical observation that the natural noon
cycle is 24 hours exactly -
http://en.wikipedia.org/wiki/Image:Tiempo_sid%C3%A9reo.en.png
Astronomically,that graphic is more shocking than believing in a flat
or stationary Earth but apparently you are prepared to beleive it.
> Are you saying that RA and Dec aren't the best system for
> celestial coordinates -- and, if so, how can we do it better?
>
I have no problem with the observational convenience of the Ra/Dec
system,.none whatsoever,just so long as it is not used to express the
axial and orbital motions of the Earth.The dominant concept for axial
and orbital motion believes that it does -
http://hypertextbook.com/facts/1999/JennyChen.shtml
If Greg really wants to make his software stand out from programs like
Google Sky,he promotes the Ra/Dec coordinate system as nothing other
than an observational convenience and then he promotes the actual
Equation of Time system which keeps clocks in sync with the axial
cycle and terrestrial longitudes at 24 hours/360 degrees as a
complimentary extension of Copernican reasoning.
> If we no longer use constellations for defining regions of
> the sky -- maybe a fanciful device from a certain perspective,
> but a very practical one -- then what is your alternative.
> How do we use it from evening to evening. What's the learning
> curve like, and how can we write guide for newcomers to
> astronomy that will get them oriented with this new and
> improved system?
>
The use of constellational geometry to determine objects is fine if
all you are doing is magnifying objects.It is not fine for structural
astronomy such as heliocentric reasoning.
On page 86,Kepler plots the positions of Mars against the
constellations from an orbitally moving Earth -
http://mitpress.mit.edu/journals/pdf/POSC_13_1_74_0.pdf
The intricate reasoning which extracts elliptical orbital geometry by
comparing the motions of Earth with that of Mars requires an accurate
view of the Earth's orbital motion yet the 'sidereal time'
justification for the Earth's orbital motion keeps it constant from
one cycle to the next represented by 3 minutes 56 seconds -
http://en.wikipedia.org/wiki/Image:Tiempo_sid%C3%A9reo.en.png
> To this I would add a bit of advice, which it seems to me
> would promote both the reality and appearance of balance in
> assessing the contributions of such esteemed figures as
> John Flamsteed, the first Astronomer Royal, and also Isaac
> Newton.
>
Newton built his ballistic agenda on Flamsteed's astrological
framework and you have no idea of the damage done to the works of the
great astronomers never mind the terrible consequences for future
productive avenues. Astronomy has clear geometric foundations and I
assure you the awful mistake by Flamsteed surfaces in your inability
to recognise that clocks in tandem with external references,such as
the return of a star,cannot be used to justify the Earth's axial and
orbital motion.
It means you cannot tell correctly where the 24 hour day comes from.
> First, the fact that an astronomer's assumptions may now be
> seen as outdated or even comically mistaken (like Galileo's
> insistence that the tides are a "necessary demonstration" or
> proof positive of the Earth's diurnal motion, rather than
> a result primarily of the gravitational force of the Moon)
> does not diminish the importance of that person's
> achievements.
>
When you can determine accurately how the human devised principle of
the 'average ' 24 hour day was transfered to a 'constant ' axial cycle
in order to keep clocks in sync with terrestrial longitudes at 24 hour/
360 degrees then come back to me and I will explain how Newton jumped
the tracks with Copernican retrogrades.
Again,if you cannot be trusted with basic astronomical principles then
how woyuld you manage with more complex.
> Secondly, the fact that some of our conventions may still
> follow 17th-century (or earlier) patterns does not mean that
> people take Newtonian mechanics as infallible. Surely you
> are aware that Einstein's theories have superceded Newton's,
> which remain very useful, for example, for studying motion
> in situations where velocities do not reach a significant
> fraction of c, the speed of light.
>
Modern imaging and especially time lapse footage instantly jettisons
Newton's poor attempt at understanding Copernican reasoning.He was a
mathematician and not an astronomer and it shows.We see the orbital
motion of the Earth directly and that is how Copernicus resolved the
observed behavior of the other planets -
http://antwrp.gsfc.nasa.gov/apod/image/0112/JuSa2000_tezel.gif
Poor Isaac created a hypothetical observer on the Sun to resolve what
can only be observed from recognition of an orbitally moving Earth -
"For to the earth planetary motions appear sometimes direct,
sometimes stationary, nay, and sometimes retrograde. But from the sun
they are always seen direct, " Newton
Look at the actual images again -
http://antwrp.gsfc.nasa.gov/apod/image/0112/JuSa2000_tezel.gif
If you see an orbitally moving Earth then congratulations,you are a
heliocentric astronomer,if you appeal to a hypothetical observer on
the Sun to resolve apparent motion then you are a Newtonian astrologer
with all the trimmings.
> To borrow a fine medieval phrase, observational astronomy
> remains in good part a question of "saving the appearances" --
> that is, building mathematical models (like RA/Dec) that will
> accurately predict what one will see in the sky.
>
'Predictions' using the constellational framework have been there for
millenia,what was new with Copernicus and Kepler was to make orbital
comparisons to extract information about the Earth's motions ,solar
system structure and a sense of scale to the cosmos.The Ra/Dec system
loses that,you get your celestial peep show but that is about all.
> Thus in s.a.a., I would suggest that some articles explaining
> how you would chart the sky or specify time for observation
> would help us get a more concrete grasp of your alternative
> approach, and possibly also try it and offer feedback as to
> our experiences, which is very much what this group is about.
>
> Most appreciatively,
>
> Margo Schulter
> mschul...@calweb.com
> Lat. 38.566 Long. -121.430
Your concerns do not rise much above magnification whereas I have
tried to show just how sprawling astronomy actually is,not just
structurally and in terms of the timekeeping systems but historically
as well.I have looked at the fiction surrounding astronomical
discoveries and how they have been directed towards empirical
agendas,to all intents and purposes Newton takes the role of
inheriting the works of Copernicus,Kepler and Roemer when the guy
basically ransacked their discoveries to suit his careless agenda..
So,you can see the progress of astronomy since the emergence of
empiricism,the heavy use of geocentric constellations,the inability to
appreciate how the 24 hour cycle was extracted from the natural noon
cycles and the failure to acknowledge the Copernican insight for the
orbital motion of the Earth as a way to explain apparent
retrogrades,these two are the biggest casualties of the late 17th
century tampering.
|
| | |
Date: 30 Aug 2007 17:37:23
From: Margo Schulter
Subject: Re: Using transits properly
|
oriel36 <geraldkelleher@yahoo.com > wrote:
> Your astrological Ra/Dec system tries to turn the stable principles
> on its head by trying to gauge axial rotation directly by using the
> return of a star to a meridian .It means that you cannot explain or
> understand where the 24 hour cycle comes from,how it elapses
> seamlessly from cycle to the next and ultimately into the wider
> practicalities of clocks and how they are used for civil purposes.
Please let me thank you for taking the time to engage in friendly
dialogue, as also with another article to which I've just responded.
As I see it, RA/Dec is merely a convenient system, and in fact
illustrates how the sidereal day is about 4 minutes shorter than
24 hours.
> The Ra/Dec framework is only an observational convenience,it is
> totally astrologicval in content and character and I assure you it is
> not and never will be a working principle for astronomy.
Well, I see it as _precisely_ "an observational convenience."
> It was Flamsteed who make that awful mistake of tying axial rotation
> directly to the return of a star in 23 hours 56 minutes 04 seconds -
>
> "... our clocks kept so good a correspondence with the Heavens that I
> doubt it not but they would prove the revolutions of the Earth to be
> isochronical..." Flamsteed
>
>
> You really have no idea just how shocking that statement is do you ?.
Maybe learning a bit about the history of science has made me hard
to "shock." While Thomas Kuhn's view of scientific developments
involving the creation, "normal" research within, and change of
paradigms is controversial, I would say it nicely illustrates how
worldviews do change. Also, just as in certain legal systems there
is a principle of _stare decisis_ or "standing by things decided"
unless/until there is compelling reason to alter them, so in science
as analyzed by Kuhn, there is a tendency to "stand by" established
paradigms until the anomalies clearly justify a consensus that
recognizing a "revolution" or paradigm change is in order.
Thus I know that Galileo, in a famous debate about the comets of 1618
with Father Horatio (or Orazio) Grassi, took what we now know is the
wrong side of the argument, asserting that comets were mere
meteorological phenomena rather than celestial objects from beyond
the Moon's orbit. More regrettably, Galileo had considerable literary
fun at Grassi's expense (astronomical disputations then, as on Usenet
today, sometimes skirting the territory of what might be called
personal abuse). Should I be "shocked"? -- or merely learn that
scientists are fallible.
The "untidiness" of the material, from a certain point of view, can
arise in various disciplines -- for example, music, where 12 pure
fifths at a ratio of 3:2 slightly exceed 7 pure octaves at 2:1, the
famous Pythagorean comma (maybe a bit like the difference between
the sidereal day and 24 hours). These differences may be ignored,
catered for, or "tempered out" in various ways.
Should I be shocked that in 1618, the year of those brilliant
comets and also a rich decade for Kepler, an Italian musician
and theorist named Fabio Colonna published a fascinating book
on his harpsichord with 31 notes per octave in which he asserted
that using a standard tuning (likely based on four slightly
narrow fifths yielding a pure major third at 5:4), the octave
would be divided into 31 equal parts -- when we now know that
those parts would in fact be slightly unequal?
To me, these small anomalies, commas, or "untidinesses" as we
might see it from a certain point of view aren't shocking, nor
the fact that scientists and musicians don't always write precisely,
or have the necessary tools and information to do so as we would
now judge the "precise" situation.
> I am almost certain that there are a few people here who are capable
> of disengaging the calendrically based observational convenience of
> the Ra/Dec system from heliocentric reasoning insofar as the
> reasoning which led Flamsteed to his muddleheaded conclusion for axial
> rotation requires a nonsensical observation that the natural noon
> cycle is 24 hours exactly -
>
> http://en.wikipedia.org/wiki/Image:Tiempo_sid%C3%A9reo.en.png
>
> Astronomically,that graphic is more shocking than believing in a flat
> or stationary Earth but apparently you are prepared to beleive it.
Certainly I know that the sidereal day is about four minutes shorter
than 24 hours -- as the changes in the sky outside my observatory
show quite pragmatically. I also assure you that I regard the Sun
as the focus of the planetary orbits. As far as I know, Newton,
Flamsteed, etc., sought to follow a Copernican and Keplerian
outlook, whatever their imprecisions or infelicities as you
view them.
Then, again, in 1814 if I recall the date of the article correctly,
William Herschel attempted to sum up his experience of observing
and classifying 2500 or so nebulae with state-of-the-art techniques
(and he had what would now be called here a case of "aperture fever,"
craving for bigger and better telescopes and pushing the envelope
as well as his allotted budgets to build them) by positing an
evolutionary theory of these objects. Unfortunately, as we now
recognize, he regarded what we classify as open and globular
star clusters as well as galaxies as objects of the same order,
and thus possibly as all "life history" stages that might be
exhibited by a given system.
Today we would say that he was absolutely right in taking an
evolutionary approach, as in the preface to one of his catalogs
(1789, his second catalogue of 1000 nebulae), where he compares
the universe to a "luxuriant garden" where, by observing plants
at different stages of growth, we can, in effect, extend our
time perception.
However, since galaxies and their components such as open or
globular clusters weren't yet recognized as in distinct
categories, his attempt to propose a specific sequence of
evolution proved less than accurate. Indeed, it was only
with Leavitt's discovery of the Cepheid "standard candle"
and the application of this to the Cepheids of M31, for
example, that the nature of our own galactic Local Group
was revealed (see the famous Shapley-Curtis debate as
late as 1920 or so, just before this clarification).
If Herschel had had this information available in 1814,
then obviously his evolutionary scheme would have been
different, and possibly more accurate as we now judge it.
>> Are you saying that RA and Dec aren't the best system for
>> celestial coordinates -- and, if so, how can we do it better?
>>
>
> I have no problem with the observational convenience of the Ra/Dec
> system,.none whatsoever,just so long as it is not used to express the
> axial and orbital motions of the Earth.The dominant concept for axial
> and orbital motion believes that it does -
>
> http://hypertextbook.com/facts/1999/JennyChen.shtml
Maybe I'm not getting this, but I read this source as saying
that a sidereal day is shorter than 24 hours by about 4 minutes,
which sounds accurate enough. Is there a disagreement here about
any relevant facts, or just about the most felicitous way to
state them?
> The use of constellational geometry to determine objects is fine if
> all you are doing is magnifying objects.It is not fine for structural
> astronomy such as heliocentric reasoning.
As I see it, constellational geometry is fine for naked eye as well
optically aided observation, or pointing a device registering other
electromagnetic wavelengths also.
> Your concerns do not rise much above magnification whereas I have
> tried to show just how sprawling astronomy actually is,not just
> structurally and in terms of the timekeeping systems but historically
> as well.I have looked at the fiction surrounding astronomical
> discoveries and how they have been directed towards empirical
> agendas,to all intents and purposes Newton takes the role of
> inheriting the works of Copernicus,Kepler and Roemer when the guy
> basically ransacked their discoveries to suit his careless agenda..
Please let me clarify first, that as I see it, an astronomer's business
may be summed up in the fine phrase "minding the heavens" -- and seeking
to understand their "construction" and dynamics.
Maybe I should clarify a small point: even in narrow technical terms,
the purpose of a telescope is not merely to "magnify," but to gather
more light than the unaided human eye can collect from remote objects.
Thus William Herschel speaks of "the power of penetrating space" which
telescopes have in proportion to this light-gathering ability.
Indeed it is a commonplace on s.a.a. and elsewhere that a newcomer
to observational astronomy may often be under the impression that
a telescope is rated by its "power," a misconception promoted by
advertisements for certain telescopes claiming very high
magnifications such as "675X." In fact, aperture is the better
index of "penetrating power," as William Herschel very lucidly
and engagingly explains in an article on this subject. It is
quite possible to use a telescope at magnifications where the
light-gathering power is inadequate to resolve detail adequately;
which is why advertisements for small refractors at "675X" or the
like may be literally accurately, but practically very misleading.
Thus I would say that the concern of an astronomer is not mere
"magnification," but rather resolution -- to shed more light on
an object or celestial system, often optically but above all
intellectually.
With the greatest admiration for Roemer (who made the first
astronomical estimation of the speed of light in 1676) and
his predecessors and contemporaries such as Huygens (a great
figure in astronomy and the theory of musical intonation
alike), I would say that if we consider "just how sprawling
astronomy actually is," then Newton's encompassing agenda
can hardly be described as "careless."
Einstein, whose Special and General Relativity can be seen
at once as superceding and consummately refining Newton's
system, offers a more just appraisal when he writes of this
great mathematician's and scientist's greatness. The calculus
(whose formulation he shares with Leibnitz, of course) and
the theory of universal gravitation are awesome achievements,
whatever the niceties of stating and explaining a sidereal
day.
This isn't to say that the latter isn't worth pursuing: I
intend to look at your posts again on Deja News (aka as
Google Groups), where I can more easily download and
study your linked documents, which may make me a better
astronomer and more capable participant in this dialogue.
Most appreciatively,
Margo Schulter
mschulter@calweb.com
Lat. 38.566 Long. -121.430
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Date: 28 Aug 2007 14:54:38
From:
Subject: Re: Using transits properly
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Margo Schulter wrote (in response to oriel36/Gerald Kelleher):
> Hi, there, and I certainly do want s.a.a. to thrive, and
> serve as a place where people can learn, share, and refine
> the best observing techniques. This is where I am coming
> from in offering the following comment.
Margo, Oriel/Gerald Kelleher is a write-only poster. It is next
to pointless to convince him to participate constructively on
SAA.
>From MOPFAQ (link below):
Q. What is the deal with [insert nut]?
A. [snip]
Gerald Kelleher (aka oriel36) is a celestial mechanics nut who thinks
that astronomy should have stopped with Kepler, and never gone on to
the
analytical universe of forces and accelerations put forth by Newton.
He
seems quite taken with the elegance and beauty of the music of the
ellipses that Kepler recorded. Whenever a thread on celestial
mechanics
(or indeed anything having to do with celestial motions) comes up, he
can be counted on to throw in his two cents worth, usually denigrating
any competent contributor who's moved beyond the 17th century. He
wastes no time reading any rebuttals to his posts, so there's no point
wasting any time writing them. He also starts a few threads of his
own,
whenever it seems that interest in 16th-century celestial mechanics
might be flagging.
*****
I'm sure Gerald will take offense. Sorry about that.
--
Brian Tung <brian@isi.edu >
The Astronomy Corner at http://astro.isi.edu/
Unofficial C5+ Home Page at http://astro.isi.edu/c5plus/
The PleiadAtlas Home Page at http://astro.isi.edu/pleiadatlas/
My Own Personal FAQ (SAA) at http://astro.isi.edu/reference/faq.html
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Date: 28 Aug 2007 20:50:14
From: Margo Schulter
Subject: Re: Using transits properly
|
oriel36 <geraldkelleher@yahoo.com > wrote:
>
> You want this forum to thrive or not ?.
>
Hi, there, and I certainly do want s.a.a. to thrive, and
serve as a place where people can learn, share, and refine
the best observing techniques. This is where I am coming
from in offering the following comment.
For some time I have been reading your posts, which seem to
strive for some kind of new or alternative paradigm for
mapping the celestial sphere and timekeeping. To the degree
that this effects practical observing techniques, like how
one specifies and locates the coordinates for a given object
of interest (say M31), it _is_ relevant to the specific
charter of s.a.a.
While many of your posts seem to decry the methods of certain
noted astronomers, including John Flamsteed, who along with
his wife and assistant Margaret Flamsteed (for whom my 20cm
Dob is named) compiled a great star catalogue, and also
unknowingly discovered the Georgian planet (also known as
Uranus) as "34 Tauri" in 1690, the question that I and
possibly others here might ask is: "What is your alternative?
Show us how it would work for our night-to-night observing."
Are you saying that RA and Dec aren't the best system for
celestial coordinates -- and, if so, how can we do it better?
If we no longer use constellations for defining regions of
the sky -- maybe a fanciful device from a certain perspective,
but a very practical one -- then what is your alternative.
How do we use it from evening to evening. What's the learning
curve like, and how can we write guide for newcomers to
astronomy that will get them oriented with this new and
improved system?
To this I would add a bit of advice, which it seems to me
would promote both the reality and appearance of balance in
assessing the contributions of such esteemed figures as
John Flamsteed, the first Astronomer Royal, and also Isaac
Newton.
First, the fact that an astronomer's assumptions may now be
seen as outdated or even comically mistaken (like Galileo's
insistence that the tides are a "necessary demonstration" or
proof positive of the Earth's diurnal motion, rather than
a result primarily of the gravitational force of the Moon)
does not diminish the importance of that person's
achievements.
Secondly, the fact that some of our conventions may still
follow 17th-century (or earlier) patterns does not mean that
people take Newtonian mechanics as infallible. Surely you
are aware that Einstein's theories have superceded Newton's,
which remain very useful, for example, for studying motion
in situations where velocities do not reach a significant
fraction of c, the speed of light.
To borrow a fine medieval phrase, observational astronomy
remains in good part a question of "saving the appearances" --
that is, building mathematical models (like RA/Dec) that will
accurately predict what one will see in the sky.
Thus in s.a.a., I would suggest that some articles explaining
how you would chart the sky or specify time for observation
would help us get a more concrete grasp of your alternative
approach, and possibly also try it and offer feedback as to
our experiences, which is very much what this group is about.
Most appreciatively,
Margo Schulter
mschulter@calweb.com
Lat. 38.566 Long. -121.430
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