Mostly clear skies this morning made for a wonderful last occultation of Aldebaran till 2033. I stood along the shore of Lake Superior in Duluth and contemplated for a moment what that year might look like should I be fortunate enough to live so long. When the image of a man steadying himself with a cane flashed by, 2018 bonked me back to the moment.
The crescent moon rose squished like someone had tried to pinch the horns together; Aldebaran shined just below its lower left edge. I couldn’t see the star with the naked eye, but binoculars showed it along with some extra red coloration from low altitude. The moon, a beautiful cantaloupe orange, cast a dagger-like path across the water. The bright part on the left was the reflection from the sunlit crescent; the fainter, wider portion from the ghostly, earth-lit half of the moon.
Through my telescope, air density and turbulence in the belly of the sky roughed up the images, turning Aldebaran into a flashing disco ball of red-and-green light. At 3:30 a.m. Central time, the star went pfft! behind the edge of the advancing moon. Just like that, the crescent stood alone and a little less lively for having lost its companion.
21 minutes later, I eased back against the hood of my car, binoculars pressed to my eyes, and waited. I knew that within a minute Aldebaran would reappear along the dark, earth-illuminated lunar hemisphere. And it did, but instead of the star popping out from behind the edge, it looked more like the moon stepped out of the way. I’ve never had that impression before.
Now, with the moon higher up and free of the horizon much, Aldebaran came instantly into view with the naked eye, shining in spectacular fashion as it kissed the moon’s dark limb. Dawn with its big crayola box colored the eastern sky red, blue, yellow and orange, but the star stubbornly refused to submit to the coming light. 45 minutes before sunrise I could still see it.
After an early rise for an astronomical outing, it can be hard to get back to bed, but not this time. Sleep occulted my busy brain nearly as fast as the moon blanked Aldebaran.
The moon never sleeps. Come this weekend, a brand new, super-thin evening crescent slides just 2° above Mercury on Saturday and only a ½° from Venus for the western half of the country on Sunday evening. Observers in the eastern half will still see a close pairing, but moon and planet will be a little further apart at 1°. How nice that all these great conjunctions are happening in the summer, when it’s easy to get outside.