the center, if it would be possible to
compute the circumference that way. Something worth investigating...
Jeff Adkins
"Frans W. MAES" wrote:
> Hi all,
>
> Just to relieve the recent boredom of this list, how about this one:
>
> As some of you may know, I have an analem
pe it is not the case !
>
> Even if I'm only a reader of tese very interresting exchanges, it gives
> me many pleasure and knowledge.
>
> Gnomonically yours !
>
> Alain MORY
> 7°E 48°N
Content-Type: text/x-vcard; charset=us-ascii;
name="Astronomer.vcf"
Content-
the shape of the earth's elliptical
orbit
to some degree of accuracy. You can also get the perihelion and aphelion
distances
and dates from this sort of data.
Jeff Adkins
"Richard M. Koolish" wrote:
> >From the web page:
> >http://sunearth.gsfc.nasa.gov/ecl
f the tip of a gnomon can only be one place at a time.) I think
Fer de Vries' picture he posted on the list makes the explanation of this
double-valued solution quite clear.
Cheers,
Jeff Adkins
Astronomical Photometry by Henden and Kaitchuck, (c) 1982 p.121
Spherical Trigonometry by W.M.
susan
(rotating turntable) you can see the difference; the 21,000 year figure is for
the time it takes the lazy susan to rotate. The 28,000 year figure is the time
for one wobble of the top.
How's that?
Jeff Adkins
Andrew Pettit wrote:
> There have been two recent subjects dealing, ac
grees between the two. I am sure there are
others on the list who can tell you the value more precisely as it probably
changes a bit from year to year.
Jeff Adkins
Achim Loske wrote:
> Dear Friends:
>
> The Earth travels around the Sun along an elliptic path. The mayor axis of
> th
d a figure eight instead of a line. This is
> the analemma. Many globes have it traced already at the right declinations,
> at noon on the International date line.
>
> Hope this helps.
>
> Ross Caldwell
> __
> Get Your Private, Free Email at http://www.hotmail.com
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Jeff Adkins
Location: 38.00 N, 121.81 W
CA, USA, Earth, Sol III
inclination, its
eccentricity, and so on. The moon's orbit also precesses over time. I suspect
that if these factors were taken into account (and it'll take a better
mathematician than I do it from scratch) the moon's position wouldn't even
match up again precisely anyway.
u a foot in the
door compared to just a few years ago.
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Jeff Adkins
Location: 38.00 N, 121.81 W
CA, USA, Earth, Sol III
Here's a few more rules of thumb.
Jeff Adkins
Holding your hand at a 90 degree angle, wrist bent up, fingers splayed apart,
at arm's length, the distance from your thumb to the tip of your small finger
is about 20 degrees.
The width of a closed fist is about 10 degrees.
The wi
or by level of difficulty (easy to hard).
Jeff Adkins
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Jeff Adkins
Location: 38.00 N, 121.81 W
CA, USA, Earth, Sol III
d in a perfect circle with no axial tilt, the
analemma would collapse to a point, and all simple equatorial dials would be
perfectly accurate, all the time.
Jeff Adkins
John Carmichael wrote:
> Hello again:
>
> In light of Luke's very clear and informative explanation of how a planet&#x
, which I believe is proprietary.
It also has the advantage of being available in a great many different
languages.
Jeff Adkins
Import file formats:
PICT, Startup-Screen, MacPaint, TIFF
(uncompressed, packbits, CCITT3/4 and
lzw), RIFF
by US mail to those NASS members who
> > aren't on the net asking them for their questions. You guys could really
> > help us out if you'd only send me a few good sundial questions. Any
> > question is ok to submit, even or especially some of the questions that
> have
> > appeared previously on the sundial list.
> >
> > PLEASE HELP!
> >
> > John Carmichael
> > 925 E. Foothills Dr.
> > Tucson Arizona 85718
> > USA
> > e-mail: [EMAIL PROTECTED]
> > tel: 520-696-1709
> >
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Jeff Adkins
Location: 38.00 N, 121.81 W
CA, USA, Earth, Sol III
a related point, consider this:
What about going back to simple solar time? With today's digital technology
clocks could be made "retro" so as to display sundial time as a function of
date,
as opposed to making sundials try to display "clock" time!
Something to think about.
Jeff
A similar human sundial exists on the sidewalk at the entrance to the
planetarium on the campus of the University of Arizona, Tucson, USA.
Complicating the design is the the fact that the sidewalk isn't level; nor is
it flat.
Jeff Adkins
"Mr. D. Hunt" wrote:
> On Mon 25
und in many model celestial spheres
suspended within a transparent globe of stars.
You could then tell what time it was in other locations at a glance.
It would even compensate for latitude differences and seasonal differences
automatically.
Hmmm
...there's a sundial design in there somewhere.
Jeff Adkins
.
I have to go now, I need to do some calculations for a analemma-shaped gnomon!
Jeff Adkins
Luke Coletti wrote:
> Hi Jeff,
>
> Welcome to the list, its a lot of fun! I thought I'd send you two
> URL's
> regarding the question about equation of time compensatio
hard to get to if you are
driving on I-64 between Lexington and Louisville, Kentucky, USA. I'd
say it would take you less than an hour from Lexington and perhaps a bit
more than an hour from Louisville.
jeff adkins
[EMAIL PROTECTED]
Hi,
I'm new to the list too. But I'll attempt to answer your questions.
My responses are preceded by --
Jeff Adkins
[EMAIL PROTECTED]
rodandkellyheil wrote:
My first
question is What meridians require no longitudinal adjustment? In
other words, are time zones constructed so th
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