Lunar occultation of Aldebaran
The Wikipedia entry for the star Aldebaran contains the following image:
http://en.wikipedia.org/wiki/File:Occultation.jpg

Based on the information on this page (e.g. image was created in July 1997) and after some trial and error with Excel (see screenshots below) I came up with the following plausible coordinates in time and space at which this image may have been created:
New Orleans area: 30N 90W
UT: July 29, 1997, 10h 08m 30s
This really is only one out of many possible solutions, which I did not investigate further. I neglected refraction which would have a small effect for such a tiny lunar distance (center-to-center topocentric LD = Moon SD = 15.5') and the overall achievable accuracy in this exercise (no obviously visible refractional flattening of Moon's disk). Parallax is important (center-to-center geocentric LD = 34.4')
Accompanying data look consistent with everything else:
The Moon age (25 days, "waning crescent") and phase (23% or about 1/4 illuminated)
Local time (UT-6h) => around 4am, about an hour before sunrise ("predawn")
The two bodies would have appeared due east at an altitude of roughly 34 degrees.
moon.xls:

aries_stars.xls:

ld_prec.xls:

intercept.xls:

http://en.wikipedia.org/wiki/File:Occultation.jpg

Based on the information on this page (e.g. image was created in July 1997) and after some trial and error with Excel (see screenshots below) I came up with the following plausible coordinates in time and space at which this image may have been created:
New Orleans area: 30N 90W
UT: July 29, 1997, 10h 08m 30s
This really is only one out of many possible solutions, which I did not investigate further. I neglected refraction which would have a small effect for such a tiny lunar distance (center-to-center topocentric LD = Moon SD = 15.5') and the overall achievable accuracy in this exercise (no obviously visible refractional flattening of Moon's disk). Parallax is important (center-to-center geocentric LD = 34.4')
Accompanying data look consistent with everything else:
The Moon age (25 days, "waning crescent") and phase (23% or about 1/4 illuminated)
Local time (UT-6h) => around 4am, about an hour before sunrise ("predawn")
The two bodies would have appeared due east at an altitude of roughly 34 degrees.
moon.xls:

aries_stars.xls:

ld_prec.xls:

intercept.xls:



More detailed and accurate detective work regarding this "puzzle" is presented in this posting by "FER" on NavList, an excellent discussion platform for all things pertaining to celestial navigation:
http://www.fer3.com/arc/m2.aspx?i=116397
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