Chronology Current Month Current Thread Current Date
[Year List] [Month List (current year)] [Date Index] [Thread Index] [Thread Prev] [Thread Next] [Date Prev] [Date Next]

Re: Private Universe and the Seasons



Surely some one has done this. See below:

Mr. Cleyet,

Dance does show the changing position of the axis relative to the
celestial sky over the time range of the program (back to about 4600
bc). And of course the changing insolation of the earth with season can
be seen as well, viewing the earth from space as the date changes.
Otherwise there is no specific graphics to illustrate the concepts you
are concerned about. Certainly the concepts of orbital perspective are
well served.

Hope this helps.

Thomas Ligon

At 03:49 PM 9/22/2003 -0600, you wrote:
Tom,

Does Dance have any capabilities in the areas that this
fellow is asking about?

Chris

-------- Original Message --------
Subject: Re: [Fwd: Re: Private Universe and the Seasons]
Date: Mon, 22 Sep 2003 14:47:16 -0700
From: Bernard Cleyet <anngeorg@pacbell.net>
Organization: Squeaky People Are More Likely To Get The Cleyet

cut

Chris!

Thanks so much.

The question is: Do you have any simulations, videos, or whatever, of
the precession of the earth's pole (~39k yr. due to the moon's gravity
acting on the earth's equatorial bulge), and/or to ~ scale the effect of
the earth's tilt (pole [angular momentum vector] not perpendicular to
the ecliptic), i.e. length of day and projected area varies with the
season (creates the seasons!), and/or the mechanism of the eclipses. As
several of the posters related, students think, inter alia, the seasons
are caused by the tilt because the tilt results in the hemisphere
experiencing summer being closer to the Sun!

bc


Larry Smith wrote:

At 3:13 PM -0500 9/19/03, Frohne, Vickie wrote:


When I taught astronomy, I found that many students could NOT
understand the diagrams in the book.... They just
couldn't interpret the book illustrations. Besides, it's hard to understand
this when looking at a static page. There are some astonomy Java applets on
the Web, as well as planetarium software, that let students play around with
animations. These work somewhat better than static diagrams, but students
still can't "see" the concept until they work with 3-D models.

It might help to take your globe pencil sharpener and a beach ball,
figure out how far apart they should be according to the scale of the solar
system (based on the globe), set 'em up outside, and THEN point the axis of
the globe toward or away from the "Sun".



I agree with everything you say; I, too, use 3D models. I, too, use the
animated applets, etc. But are you furthermore saying that 2-D diagrams
must necessarily fail and we shouldn't even _have_ them in the books? Can
we make (2D) diagrams enough better than current ones to where they'd help
rather than hinder? Is it possible to make diagrams good enough so someone
could learn this concept from a book on their own?

Larry