OCCULTATION OF MERCURY 20 JULY 2012

Conditions of visibility and various information, data elaborated with WinOccult (C)



Moon: % illumination  1+, solar elongation  14░

Disappearance
                                    U.T.  Sun Moon     CA  PA  WA   a    b
Location                          h  m  s Alt Alt Az    o   o   o  m/o  m/o

AU Adelaide                       8 51 49 -12  2 288  18N  52  37 +1.0 +3.5
AU Edinburgh                      8 52 34 -12  2 288  17N  51  35 +1.0 +3.7


Reappearance
                                    U.T.  Sun Moon     CA  PA  WA   a    b
Location                          h  m  s Alt Alt Az    o   o   o  m/o  m/o

AU Albany                         9 25  2  -2 12 296 -68N 325 310 +0.1 -0.7
AU Kalgoorlie                     9 18 47  -2 12 294 -44N 350 334 -0.4 -2.4


Times in U.T.

Sun Alt the altitude of the sun. The field is blank if the sun is lower than -12 deg. (Nautical twilight)
Moon Alt the altitude of the moon
Moon Az the azimuth of the moon
CA Cusp Angle - the angle of the event around the limb of the moon, measured from the nearest cusp. -'ve values indicate a bright limb event. The cusps are usually N (north) or S (south), but near full moon can be E (East) or W (west).

If a lunar eclipse is in progress, CA gives is the % distance from the centre of the umbra, and is followed by a 'U'. Values up to 103% are possible. Where an event occurs more than 103% of the umbral radius, the usual Cusp Angle value is displayed.
PA Position Angle - the angle of the event around the limb of the moon, measured from true north
VA Vertex Angle - the angle of the event around the limb of the moon measured anticlockwise from the vertex of the lunar limb - i.e. the point on the limb highest from the horizon
A coefficient for correcting the prediction for changes in site location. The units are minutes of time per degree (or seconds of time per minute of arc). The correction to the prediction for a change in site, in seconds of time, is found by multiplying A by the change in site longitude (+'ve for changes towards the East) from the prediction site.
B same as for A, but for changes in latitude (+'ve to the north).


Data generated with software WinOccult (C)