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Occultation of the Pleiades


 

We had a cold but fun night with the moon going through the Pleiades giving us a life time of lunar stellar occultations. ? The first star, Electra,? was covered by the moon around 1947 or so. At 3.7 magnitude it was fairly easy to see against the bright moon. The limb of the moon could not be easily seen due to the moon phase. Only a thin strip of the lunar surface was in the dark. The best occultation was Maia at 3.9 magnitude. That was a grazing occultation that was the most spectacular. It rode the limb of the moon so close I could see it through the peaks. Every time I thought it would be gone it would peak out Just visible on the illuminated horizon of the north region on the moon. That was the best graze I have ever seen. A real cliff hanger.?
Alcyone was the last we watched as the moon went through the center of the cluster.

I used my 120 Stellarvue LOMO Doublet as it has incredible contrast. It is amazing how the human eye can handle contrast in light intensity far beyond what a camera can do as Kent said in his post. The choice of EP was the 40 mm Pentax giving quite a wide field at a bit less the 20 power. The entire cluster could be seen in one fov.? Big binoculars would have done well also. One nice thing was I was able to reverse my sliding counterweight to perfectly compensate for the heavy eyepiece and was able to balance the scope for effortless movement. Those huge eyepieces can be a problem there due to weight.?

We switched to Jupiter to see a shadow transit of Io and the moon Ganymede going behind the planet high in the polar region. That was quite good as a bonus.

Mars showed better surface albedo features than the past month but seeing somewhat hampered the steady view. Mare Boreum was obvious as was Acidalium, a dark feature hanging off Boreum. Detail though was a bit obscured by seeing.

34 degree temps did not dampen the spirits but did make the fingers pretty cold during assembly and disassembly of equipment. A really fun evening.