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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 center of motion for the
Sun
and the the
Sun
as the center of motion for the
planets
(i.e., a modern version of the
Tychonic system
) and then the
Sun
as the general center of motion (i.e., 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
center-of-mass inertial frame
of the
Solar System
(which is unrotating with respect to the
observable universe
). In
inertial frames
, accelerations always require physical causes which are
forces
. The
Moon
is
NOT
shown. Short enough for the
classroom
.
SC E01: Claudius Ptolemy- The Greek Astronomer | 1:08
: The short intro. Seems OK.
NOT
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
.