Key to lunar occultation prediction - double stars
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day: day of the month of the event. A prefix 'A' (from "Alert") means no available observations after 2010.
WDS: catalogue number of star in Washington Double Star Catalogue (check http://simbad.u-strasbg.fr/simbad/ and perform "query by identifier" for details on star).
mag1: visual magnitude of primary component.
mag2: visual magnitude of secondary component (null if unavailable).
mag: combined visual magnitude of pair.
sep: separation in seconds of arc.
typ: immersion (I), emersion (E).
limb: whether event at illuminated or dark limb.
hh.mmss: UTC of event in hours, minutes and seconds. In the pdf file, an asterisk after the value indicates that the emersion event occurs one day later than specified, and that the associated immersion event takes place at the day specified.
impact: impact parameter in units of lunar semidiameter (grazing occultation will have impact close to one,
while impact will be close to zero for occultation through or close to centre of Moon's disc).
a: longitude correction, in minutes of time per degree of longitude.
b: latitude correction, in minutes of time per degree of latitude.
illum: percentage of Moon illuminated. Positive: waxing Moon. Negative: waning Moon.
def: defect of illumination at contact (radial distance from contact to terminator), in seconds of arc. Calculated in events at dark limb.
PA: position angle of event in degrees, measured from north celestial pole in the positive sense (eastward).
Please note this is NOT the position angle of the double star.
P: position angle of lunar north pole in degrees, measured from north celestial pole in the positive sense (eastward).
C1: position angle of first cusp, measured from north celestial pole eastward and defined as first cusp from subsolar point in the positive sense.
C2: position angle of second cusp, measured from north celestial pole eastward and defined as second cusp from subsolar point in the positive sense, or first cusp from subsolar point in the negative sense.
hS: height of Sun above local horizon, in degrees.
hM: height of Moon above local horizon, in degrees.
AM: azimuth of Moon along local horizon in degrees, measured from S westward.

NOTE: the duration of the observed step in the light curve (if any) depends on a number of factors. For an event at impact = 0, such that the line between the two components and the Moon's apparent velocity (assumed to adopt its mean value) are parallel, and assuming a smooth lunar surface, the duration is roughly given by 1.82 x sep in seconds of time, where sep is the pair separation in seconds of arc. This should be an upper bound for the actual duration observed.