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Ptolemy videos
(i.e.,
Ptolemy (c.100--c.170 CE)
videos
):
High cal ones:
Ptolemaic & Copernican Solar System 0:46
: Actually, this
animation
is neither the
Ptolemaic system
as set out by
Ptolemy (c.100--c.170 CE)
nor the
heliocentric solar system
as set out by
Nicolaus Copernicus (1473--1543)
. It's just simplified presentation of the planetary motions taking the
Earth
as the origin (a modern version of the
Tychonic system
) and then the
Sun
as the origin (the modern
heliocentric solar system
). Both versions are geometrically correct qualitatively. The latter is much simpler to understand and, more importantly, shows show the motions in the
free-fall
inertial frame
defined by the
Solar System barycenter
which is unrotating with respect to the
observable universe
. In
inertial frames
, accelerations always require physical causes which are
forces
. Short enough for the
classroom
.
SC E01: Claudius Ptolemy- The Greek Astronomer | 1:08
: The short into. Seems OK. No appropiate for the
classroom
.
Ptolemaic Cosmology | 1:00:44
: The long intro. Seems OK, but
yours truly
has only scimmed it. Too long for the
classroom
.
Local file:
local link: ptolemy_videos.html
.
File:
Ptolemy file
:
ptolemy_videos.html
.