Occultation of Aldebaran by the Moon ...

This Event was for the next year the only occultation which could be observed within sufficient height over the horizon for middle Europe. The next two occultation of Aldebaran within CY 2016 will be close to the west horizon (January 20th, 2016, December 13th, 2016) close to moon set and can be observed in North America and Canada. Taking into account that weather conditions are not always ok, it was a favorable circumstance to get this event observed.
In addition, it was for me the first time to get the Image Source DMK 21 (having a small chip) working on the new telescope. I was not sure about the alignment of the mount and the resulting pointing capabilities – the bright would moon help for sure to find the target even having a small FOV of roughly 5x4 arcmin. However, it worked well!
I was limiting the frame per second (FPS) to 30 not sure about the exact entry time as well the resulting filesize using 60 FPS.

Aldebaran Occultation December 23th, 2015
IS DMK 21 @ Newton 510/2150mm
Luminance, 1/5000s, Gain 600
Orientation: North->Up, East->left.
(klick on image for short video sequence - shown in a separate tab)

Not having enough data points resolving the decreasing brightness allows only an estimation of roughly 66ms for the time to get Aldebaran completely covered. Using as distance for Aldebaran 20pc we can deduct that Diameter of this star is 74 times larger than the Sun. Values reported from references indicates ~ R(Aldebaran) = 44 R(Sonne).

To get more data points next time measurements will be done @ 60 frames per second. A model how the lightcurve should looks like will be developed.


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