Have you taken your Aldebaran-moon pill lately? Better do it soon, the prescription is running out. The series of occultations of the bright star Aldebaran by the moon that began in 2015 will finish up next month at least for U.S. observers. Two remain in 2017: The first occurs during early evening hours Sunday night, November 5th for the eastern two-thirds of North America; and the last on December 30th, again during evening hours for the eastern United States. The next series won’t begin until 2033, 16 years from now!
From the U.S., Sunday’s event happens with the waning gibbous moon low in the eastern sky. The star will disappear at the moon’s left or east side and reappear on the right (west) around an hour later depending on your location. For times for many cities in the “occultation zone,” click the Nov. 5 link above.
Times are given in UT or Universal Time. Since we lose Daylight Saving Time early Sunday morning, we’ll be back on Standard Time Sunday night. Subtract 5 hours from UT for Eastern time, 6 for Central, 7 for Mountain and 8 for Pacific. A small telescope is best for viewing the delightful and sudden disappearance and reappearance of Aldebaran.
We’re entering a particularly dry period for bright star occultations. After the final Aldebaran occultation on September 3, 2018 (visible in Greenland and the Arctic), no first-magnitude star will be occulted by the Moon until August 25, 2023, until Antares steps into those shoes.