View Full Version : Moon Occults Aldebaran - 2017 DEC 30-31

2017-Dec-23, 06:13 PM
The waxing gibbous Moon will occult (cover) the first magnitude star Aldebaran in Taurus for observers in Europe and North America during the night of 2017 DEC 30-31. This will be a predawn event for Europe, an evening event for eastern North America including Chicagoland, and an afternoon event for western North America.

The current series of 49 monthly Aldebaran occultations extends from 2015 JAN 29 to 2018 SEP 03. However this will be the last one in this series visible from Chicagoland and most of North America. The next series will commence on 2033 AUG 18.

Immersion will occur on the lunar dark limb and emersion on the bright limb. An observer on the only graze path will witness the star winking on and off as lunar hills and valleys pass by. Those north of the graze path will see a full occultation.

Iíve created a graze map, a set of Besselian elements for computer input, and preview graphics with data for Chicago. They can be seen by visiting my Occultations webpage at www.CurtRenz.com/occultations.html

Photos and descriptions of the occultation would be welcome additions to this thread. If you would like specific occultation or graze predictions for your location, please reply to this post with your longitude, latitude, elevation and time zone.

2017-Dec-30, 06:09 PM
Tonight's the night. :)

This will be the last nighttime lunar occultation of a first magnitude star or bright planet seen from Chicagoland until 2020. The next will be the immersion only of Mars before sunrise on 2020 FEB 18, and both occultation events for Mars during the evening of 2022 DEC 07. After that will come both occultation events for the first magnitude star Antares during the evening of 2023 AUG 24. This is all essentially true for most of North America.