On the evening of September 3, 2001, the magnitude 4.4 start ZC 3425 will graze along the edge of the Full Moon as seen from the southern portion of central Wellington city, New Zealand. In spite of the brightness of the star (which is a double), because the graze occurs right on Full Moon the event will be difficult to see and large telescopes are recommended. Path details are as follows:

                            UT       
 Longitude    Latitude   h  m  s  Alt   Az    PA     WA     CA
+174 45 00   -41 16 56   8 52 49   29   76   336.8  0.53  37.86N
+174 48 45   -41 16 43   8 52 53   29   76   336.8  0.52  37.87N
+174 52 30   -41 16 29   8 52 57   29   76   336.8  0.50  37.89N
+174 56 15   -41 16 15   8 53 01   29   76   336.8  0.49  37.90N
+175 00 00   -41 16 00   8 53 05   29   76   336.7  0.47  37.91N

ZC 3425 is a double star: Mags 5.4 and 5.4, Separation 0.10, PA 90 deg.
Graze path of secondary 0.07 km North, and 0.2 sec later compared to primary.

Moon Illumination: 100%
Lunar Elongation: 173 deg.
Vertical Profile Scale: 1.96 km/arcsec
Horizontal Profile Factor: 1.56 deg/min

The graze band extends across south-central Wellington city, with the region of most interest between 2 and 4 kilometres south of the line defined above.

• The "zero" line above crosses the Wellington container terminal and the city end of Karori Road.
• The "2 km south line" crosses the summit of Mt Victoria and the intersection of Thompson St and Webb St.
• The "3 km south line" crosses Government House.
• The "4 km south line" crosses the Kilbirnie Aqautic Centre and Marilyn Head's house near the corner of Owen St and Harper St, Newtown.

Expected Lunar Profile:

The jagged dotted line shows the expected profile of the lunar limb at the point of graze. Almost all the profile will be illuminated at the time of the event. See below for observing tips. :

• The graze is 37 degrees from the NORTH cusp of the Moon. Of course, because the moon will be Full determining exactly where the north cusp might be may be a problem! However the northern limb of the Moon is the limb nearest the northern horizon. If you are observing with a telescope in which the image is inverted, or back to front, nudge the top of the telescope so that it moves towards the horizon while you look through the eyepiece. The direction in which the image moves is north.
• The star will follow a horizontal line across the profile diagram from left to right. The scale shows the approximate position of the star from 3 minutes before to 3 minutes after the graze. The vertical position of the line the star follows on the profile is governed by the position of the observer (See above).
• The star will be difficult to see next to the fully lighted moon. It is imperative that you find the star up to one hour before the event (i.e. about 7.50 pm) and follow it in. One hour before the event the star may be up to two Moon diameters away from the lunar limb.

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