I’m sorry the dogma was over the top. I retract the statement. I was wrong. As I have stated before, the distances were calculated using the Alcyone Ephemeris 3.2 software. The program is described as :
The principal source for Alcyone Ephemeris is Steve Moshier's analytical ephemeris based upon trigonometric expansions for the earth and planets and the lunar ephemeris ELP2000-85 of Chapront-Touzé and Chapront for the moon, both adjusted to Jet Propulsion Laboratory's DE404. Moshier's ephemeris is described and the files can be downloaded at www.moshier.net (see aa-56.zip and further details on aa-56.zip, which contains references to Moshier's sources, as does the Readme file in aa-56.zip). Alcyone Ephemeris is further adjusted to JPL's DE406 by a series of corrections, some optional, described below in Accuracy. Algorithms for reduction to geocentric coordinates, precession, and nutation are from Moshier, and additional algorithms are applied to compute velocities, accelerations, and transformations of coordinates, including topocentric coordinates with corrections for parallax and refraction. The ephemeris is quite fast; with an 1600mgh Athlon processor, 100 calculations of geocentric longitude, latitude, and distance for the sun, moon, and all planets take about 2 seconds, 100 calculations of differences for all of these about 4 seconds. Alcyone Ephemeris is also very compact, about 20 mgb, compared to nearly 200 mgb of data files for DE406. The following ephemeris types are independent of Moshier's ephemeris:
Apparent magnitudes of planets are computed in three ways: from formulas and coefficients of G. Müller, used in the Astronomical Almanac until 1984, from coefficients in the Astronomical Almanac since 1984, and from coefficients in tables 7.41.1 to 7.47.1 of the Explanatory Supplement to the Astronomical Almanac (1992).
Lunar libration, position angle of the lunar axis, and selenographic coordinates of the sun and position angle of the limb are from Jean Meeus, Astronomical Algorithms, 2nd ed., Wilmann-Bell, 1998.
Mean orbital elements are from Meeus, Astronomical Algorithms; these are not identical to the elements used for the ephemeris calculations although the differences, except perhaps at early epochs, are very small.
Osculating lunar orbital elements are from Michelle Chapront-Touzé and Jean Chapront, Lunar Tables and Programs from 4000 B.C. to A.D. 8000, Willmann-Bell, 1991.
Delta T. The formulas for computation of delta T and the table from the Astronomical Almanac used for interpolation, along with a discussion of methods of determining delta T, can be found at http://www.phys.uu.nl/~vgent/astro/deltatime.htm. Definitions of systems of astronomical time, including ET, UT, and more recent systems, can be found at http://www.gb.nrao.edu/~rfisher/Ephemerides/times.html.
Accuracy
There are two ways of evaluating the accuracy of an ephemeris, the first by comparison with observation, the second by comparison with other ephemerides. Since the first is impractical, and requires observations reaching an accuracy of a very few seconds, which means only of the last three centuries while Alcyone Ephemeris extends from -2999 to +3000, we have evaluated AE by comparison with JPL's Horizons ephemeris generator. This ephemeris is based on Jet Propulsion Laboratory's DE406 ephemeris, what is now considered the most accurate available long-period ephemeris.
The comparisons with DE406 are for geocentric longitude, latitude, distance (from the earth) for the planets and Moon, geocentric longitude of Sun and have been computed at intervals of 2130 days forward and backward from AD 0 Jan 1 0h at Greenwich in Ephemeris Time (ET). The result is 1025 comparisons extending from -2998 Jan 1 (JD 626038.5) to +2973 Aug 21 (JD 2807158.5). The period of 2130 days was chosen to give the maximum range of dates with the maximum number of calculations forward and back, 1025 (= 512 + 1 + 512), possible in AE. Each calculation is of the difference: Difference (AE - DE406) = AE - DE406.
The differences in the graphs are scaled in seconds; the distance is compared in astronomical units to seven places (10-7 AU) and the graphs are scaled in 10-6 AU = 0.000001 AU.
Moshier's ephemeris, upon which AE is based, was calibrated to DE404 from -3000 to +3000 for the outer planets, Jupiter, Saturn, Uranus, Neptune, Pluto, and from -1349 to +3000 for the inner planets, Mercury, Venus, Earth, Mars. In order to bring AE into better agreement with DE406 for the entire period -2999 to +3000, we have applied further corrections to heliocentric coordinates, which in turn correct geocentric coordinates. The graphs show only the corrected geocentric coordinates except for the moon, Jupiter, Uranus, and Neptune, for which uncorrected and corrected longitude is shown for reasons that will be explained below. The most notable corrections are for Mars for which the corrections extend from -2999 to +300, and Pluto for which the corrections extend the entire range from -3000 to 3000. The corrections for the earth, although much smaller, affect the geocentric coordinates of all the planets, the closer planets more, the distant planets less.
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Originally Posted by tusenfem
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Thank you. I’ll look at this further.
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Originally Posted by Nereid
Good.
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Originally Posted by Nereid
How are you so looking?
Specifically, do you have a plan concerning what to look for? If so, does that plan incorporate a pre-defined method of (statistical) analysis? a pre-defined method of objectively determining the accuracy and completeness of the datasets? and so on ...
What is the second step?Really?
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I did not know what the second step was when I started into this. I have never pursued anything like this before. The high r^2 values made it worth while to look into further. So far the exercise has been worth while. I have and am learning a lot. And yes, I think at this point I need to start defining my analysis.
The Alcyone software and JPL data are highly accurate. I do not know how to quantify the accuracy of the sunspot data. I made the statement before that the sunspot data “is what it is” acknowledging the fact that the older data had a higher level of error in it. The older historical sunspot data is not good. Solanki has stated that there data has a 68 % uncertainty. I have not used this data up to this point and if I do it will be just for a trend line and nothing more. Is this wrong?
I thank you all for your constructive feedback. I came here knowing that I was going Against the Mainstream.
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