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Determining heliacal event depending on geography and weather conditions

Weather maps (in Lambert conformal conic projection) from Wunderground (temperature and humidity) and Find Local Weather (air pressure) are used. A height map (in Lambert azimuth equal area projection) of European Environment Agency has been used (this has been transformed to Lambert conformal conic projection using ArcGIS). In principle one can use any colored map with known map projection.

Excel just reads the color maps (with same map projection) and their legends and then calculates the day of a heliacal event using my Schaefer implementation (part of Swiss Ephemeris). In the below example: the first visibility of the Moon's crescent and Venus' heliacal rise. The results are presented as Charts.
Excel has to work quite hard;-) It took ~3 hours to calculated below animation (which represents some 160,000 points on the map).

First crescent day after July 30th 2011

Here is an animation of the first crescent date (which is depicting the start of Ramadan 2011; 1432 AH) on the European continent (for an experienced person using his/her naked eyes). In the animation three pictures are viewable: one with the mean AEC and pictures with the AEC reduced (-: meaning less extinction) and  increased (+: meaning more extinction) with its sigma. The more extinction the later the first crescent of the Moon will be visible at a particular location.
Animation of first crescent day depending on AEC
Day 1 is equivalent with July 31st, 2011

Remember that heliacal events are quite depending on local meteorological circumstances, so in real live differences might be observed. The above animation is not calculating the visibility under optimum meteorological circumstances; it used the 'actual' meteorological conditions.
For comparison with other criterions an optimum visibility (using AEC~0.14) has been calculated here (coloring is different then above!):
Optimum visibility (AEC ~ 0.15)
Day 0 is equivalent with July 30th, 2011

Venus' heliacal rise in 2012

Another example with the heliacal rise of Venus in 2012 (under ideal weather circumstances: AEC=0.14):
Venus heliacal rise over Euope
Day 18 is equivalent with June 9th, 2012

Comparison with other maps

We can best compare Schaefer criterion's results with the maps provided by van Gent (uses Yallop's criterion, regradless of his slightly different legend), Moonsighting (uses adjusted q-values compared to Yallop) and MoonCalc6 (uses Yallop's criterion).
Comparing the following dates:
So Gent/MoonCalc6 and Moonsighting don't give the same results and this looks to be due to the fact that Moonsighting uses different q-values for its categories.

I would not have been expected that Schaefer would be comparable to an A or a D category; I would expect it closer to a B (Visible under perfect conditions) or a C category (May need optical aid to find the crescent). This needs more study.

As I am mostly interested in benchmarking Schaefer's criterion, and a more direct check is to see how the actual sightings of Moonsighting compare with Schaefer's criterion implementation. Watch this space;-)

Acknowledgements

I would like to thank the following people for their help and constructive feedback: Alan Murphy, Frank Prendergast, Voi Pio, Leon Steijger and all other unmentioned people. Any remaining errors in methodology or results are my responsibility of course!!! If you want to provide constructive feedback, let me know.

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Last major content related changes: Aug. 5, 2011