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Old May 19th 06, 08:03 PM posted to uk.sci.weather,alt.talk.weather,uk.sci.astronomy
Weatherlawyer Weatherlawyer is offline
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First recorded activity by Weather-Banter: Dec 2004
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Default Chanchu is dead; long live pearl.


wrote:

Try this for phases:
http://www.inconstantmoon.com/index.htm. Not sure
whether timings are included for indeterminate phases.

Software like any version of the sky has also a phase tool embedded.

Nice site and it lead me back to the JPL, which seems to offer more and
more lately: http://ssd.jpl.nasa.gov/?horizons (We get bugger all from
our own people despite the hideous taxes we pay them in comparison.)

JPL produce the nautical and other almanacs in partnership with the
Rutherford Physics laboratory in Cambridge. I have looked there a few
times to try and get what I wanted but I just forgot the need I once
had and developed the ideas I have now, working with what little data
there is.

Here is a good one for the basic phases:
http://ssd.jpl.nasa.gov/?horizons: 6000 Year Catalog. When I was
working on the ideas, there was nothing like this. So I look forward to
the future with more and more confidence.

on the saros
Interesting that the Saros continues to produces effective phenomenae
for centuries. I had thought that a cycle only lasts for three eclipses
and that was the end of it.

"Every eclipse is said to belong to a Saros series, and each series
is given a number. For instance, the annular eclipse of February 1999
belongs to Saros series 140, whilst the total eclipse of August 1999
belongs to series 145. At any point in time there will be around 42
Saros series in progress.

The eclipses within any Saros series are not identical, the area they
cover gradually migrates, each eclipse being centred slightly to the
north or south of its predecessor.

This gives a saros series a fixed life span, beginning as a minor
eclipse near one of the poles, evolving cycle by cycle into a major
eclipse spanning the equatorial regions, and eventually ending as
another minor eclipse at the opposite pole.

By convention, the odd numbered series begin near the north pole and
migrate southwards whilst the even numbered ones move northwards from
the south pole.

The lifetime of a Saros, from pole to pole, is some 1400 years, during
which it will produce between 69 and 86 eclipses. Saros 145 began in
January 1639, and will end in April 3009."
http://www.inconstantmoon.com/inconstant.htm