Showing posts with label occultation series. Show all posts
Showing posts with label occultation series. Show all posts

Monday, October 24, 2011

Occultation of Mercury: October 28, 2011

The third and final occultation of 2011, Mercury's occultation this October 28, 2011 will be an astronomical treat for those in Australia, New Zealand, & southern Oceania. Although it was a true fact that each of these occultations this year (2011) were poor to view, 2012 brings yet another smorgasbord of events, as listed at the end of this article.



"It will be observable after sunset from French Polynesia," the Transits Page writes in correspondence of the event. From there, the whole southern Oceanic hemisphere, centered in Australia & New Zealand, will see Mercury occult, right through the center of the Moon. This is a "central one," referring that Mercury will pass through the center of the Moon. Basic information is below.

Greatest Occultation = 2011-Oct-28 02:11:32 TT
Occulted Planet = Mercury
Occultation Series = 7560
Member = 1 of 1
Elongation from Sun = 18° E
Moon illuminated fraction = 2 %
Lunar Magnitude = -5.9
Planetary Magnitude = -0.3
Gamma = -0.21966
Gr. Longitude = 158° 31.4' E
Gr. Latitude = 32° 43.0' S
Gr. Duration = 94m 10.3s
ΔT = 66.64s

Credit: the Transits Page

This occultation occurs in the 7560 series (similar to the Saros of eclipses), and will be the best to view. Mars' Tahitian occultation in July, and Venus' Mediterranean occultation in June both occurred with poor lunar conditions, but the moon will only be two percent illuminated this time! Mercury will pass swiftly - starting on the 27th of October at 23:56 UT and ending on the 28th at 04:24 UT - four hours and twenty-eight minutes total. Below is a picture of Mercury's entrance and exit passage at the green dot in the above picture (in between Australia and New Zealand).

Credit: Transits Page
Local Circumstances—Greatest Occutation

Longitude = 160° 42' 51" E
Latitude =  32° 08' 34" S
Elevation = 0m.

Greatest Occultation = 2011-Oct-28 02:16:20.4 UT
Altitude =  77.8°
Azimuth = 353.7°
  
            Calendar Date and Time          Planet           Sun     Limb
                Universal Time         Azi    Alt    PA      Alt      PA

Ingress    2011-Oct-28 01:29:10.9 d   39.2°  74.8°  102.4°   69.7°  290.8°
Egress     2011-Oct-28 03:03:56.2 b  311.7°  72.9°  287.7°   56.0°  290.4°

Duration    94m 45.3s

Mercury's occultation is hoped to be great - so watch the Moon, if you live in the area of occultation!