Monday, April 23, 2012

Stellar Occultations for April 25-26

For two days this April, two different 3-4 magnitude stars will occult for Western Africa both times, with a plethora of other locations on each separate dates. With the moon waxing after being full April 21, the stars should not be too difficult to see and should provide a wonderful show for spectators.


The moon will only be 17% illuminated when this occultation of Zeta Taurus occurs, giving Western Europe and Africa a wonderful seat. France, Spain, Italy, Germany, (part of) England, and most of the north-western coast of Africa are just a few of the many locations (you can find ephemerides here) the occultation will be visible. Zeta Taurus is a binary star of the 3.010 magnitude on the far right side of the zodiacal constellation of Taurus, situated approximately 440 light-years from earth; although without highly-technological equipment the two stars that comprise Zeta Taurus will cannot be discerned, it is bright enough to be seen with the naked eye, but binoculars or a telescope will make the event more expressive. 


Although the visibility of the occultation is practically the same as the occultation yesterday (April 25, above), most of north-western Europe will not be able to see Gamma Gemini be occulted by the moon. With a moon illumination of 25 percent, it is the prime time for this rather-dim star to occult: it being at 4.1, according to IOTA stellar occultations, ephemerides for locations of this occultation here. Western Africa will be the prime location for this event, as most of Africa's north-western part is in the visibility zone.