Daniel,

By the way, what is this mysterious other group you keep mismailing to, and is it open to the public?

My apologies to the group as a whole and to you.  I have been juggling too many things lately and sending things out while being tired and not watching what I'm doing.  The two groups were I've made posting mistakes are - the Mathematica symbolic language listserv and the Spectrum Labs yahoo group.  Mathematica is an alternative to MathLab used at the UofU.  Unlike MathLab, Wolfram sells a $350 Home Edition. Mathematica MathGroup archive: http://forums.wolfram.com/mathgroup/ Mathematica MathGroup announce: http://smc.vnet.net/MathGroup.html      Mathematica AstronomicalData function demos      http://reference.wolfram.com/mathematica/ref/AstronomicalData.html      http://demonstrations.wolfram.com/symbol.html?symbol=AstronomicalData Spectrum Labs yahoo group http://groups.yahoo.com/group/SpectrumLab/ Spectrum lab download page http://www.qsl.net/dl4yhf/spectra1.html These all relate to current projects, listed below. Specifically I what I am trying to do was to tweak a graph of the Ursid 2010 meteor shower counts by labeling with positional solar longitudes as opposed to dates. See sample graph at - http://www.slas.us/gallery2/main.php?g2_itemId=2789 The meteor guys ( www.imo.net) also appear to use solar longitude as a proxy for the Earth's orbital position.  The daily noise source between 10 UT to 18 UT shown in the graph apparently is Salt Lake City's daily traversing under the Earth's apex-of-the-way - the direction of the Earth's orbital path.  The interplanetary dust particles are being run over by the Earth at its orbital speed of 29 kilometers per second.  That causes the increased daily background count shown in the chart between 12UT and 18UT.  The daily lows between 22UT and 06UT represent Salt Lake City traversing the antihelion (opposite the Sun) direction and away from the apex-of-the-way. I was also trying to come up with a way to find the local horizon altitude of the apex-of-the-way (90 degs longitude in advance of the solar longitude) by hour.  I have the raw data from the JPL Horizons Empheris web application, but wanted to cook the same data in my own spreadsheet. I was planning to just use solar longitude + 6 hours (90degs) as an approximate proxy for the local horizon altitude of the apex-of-the-way.

Also, if you would like a copy, you may have it.

Yes, I would love to have a copy.  I have many Meeus coordinate conversion algorithems implemented in VBA from spreadsheets built in 2006 and 2007 which were DSO and lunar oriented, but I never implemented celestial->eclipitic ecliptic-celestial coordinate conversion code.  My vba codes are in the spreadsheets here: General coordinate conversion code http://fisherka.csolutionshosting.net/astronote/plan/ObSpdht/ObSpdhtProject....  Lunar and solar positions http://fisherka.csolutionshosting.net/astronote/plan/MoonPlan/MoonSpdtProjec... My current hobby projects: 1) Radio meteor observing station - setup and debug http://www.slas.us/gallery2/main.php?g2_itemId=2774 2) Mark III allsky allweather meteor camera http://fisherka.csolutionshosting.net/astronote/atm/mcm3/mcm3.html 3) Misc astro math graphing with Mathematica http://www.slas.us/gallery2/main.php?g2_itemId=2812 Again, my apologies to the group for the misposts. Time to slow down and drink more beer. Opps - this is a family listserv. Clear Skies - Kurt