astronomy-chat.net
Promoting astronomy discussion.



Main
Date: 06 Sep 2006 06:44:39
From: oriel36
Subject: Another dynamicist myth


The discovery of Neptune as a planet is said to have occured through
'perturbations' * a word sprinkled like magic dust lately in the
meaningless definition of 'planet' debacle.The actual affirmation of
Neptune as a planet came from the periodic times argument of Kepler
through William Herschel in 1781.

http://books.google.com/books?vid=ISBN0486411508&id=L_MNFFLofXAC&pg=PA822&lpg=PA803&dq=longitude+frisius&sig=r8GlWpaNTEEZ4KBNc0bGCfw11Mk

The Keplerian periodic times argument is simple enough and certainly
withing the capabilities of many astrophotographers .No
perturbations,just clean and clear thinking which affirmed Neptune as a
planet -


Epitome Of Copernican Astronomy by JOHANNES KEPLER


Finally by what arguments do you prove that the centre of the Sun which
is at the midpoint of the planetary spheres and bears their whole
system - does not revolve in some annual movement,as Brahe wishes,but
in accordance with Copernicus sticks immobile in one place,while the
centre of the Earth revolves in an annual movement.


Argument 10


" The 10th argument,taken from the periodic times, is as follows; the
apparent movement of the Sun has 365 days which is the mean measure
between Venus' period of 225 days and Mars' period of 687
days.Therefore does not the nature of things shout out loud that the
circuits in which those 365 days are taken up has a mean position
between the circuits of Mars and Venus around the Sun and thus this is
not the circuit of the Sun around the Earth -for none of the primary
planets has its orbit arranged around the Earth,as Brahe admits,but the
circuit of the Earth around the resting Sun,just as the other
planets,namely Mars and Venus,complete their own periods by running
around the Sun."


Johannes Kepler



It seems like the dynamicists could rob an observational astronomer of
his discovery and frame it historically to suit affirmation of
'perturbative' theory -

* http://en.wikipedia.org/wiki/Neptune