2024, November 27:  Moon Occults Spica

November 27, 2024:  Before sunrise, the moon occults Spica for sky watchers across a large region of eastern US and Canada.

Venus, Mercury, Spica, and Moon, November 13, 2020
Photo Caption – 2020, November 13: Sparkling Venus – nearly 18° up in the east-southeast – is 8.1° to the upper right of the old moon and 5.5° to the upper left of Spica. The lunar crescent is 6.9° to the lower left of Spica and 5.1° above Mercury.

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by Jeffrey L. Hunt

The visibilities of the moon are described relative to sunrise and sunset.  Find those times in local sources.

Moon before Sunrise

Morning Crescent Moon, Lunar Occultation
Chart Caption – 2024, November 27: After this morning’s lunar occultation, the moon is near Spica through a binocular.

Step outside an hour before sunrise.  The crescent moon, 12% illuminated, is nearly 25° above the southeast horizon.  The star Spica is 0.4° to the moon’s upper right.

Moon Occults Spica

Earlier this morning the moon occults or eclipses the star for sky watchers in the eastern US and Canada.  An occultation is when the moon eclipses a body that has a small apparent size in the sky, such as a star or planet.  The moon occults dimmer stars continuously, although occultations of bright stars are pretty events and easily observed.  A binocular or spotting scope with magnifications around 20x are helpful. A telescope with higher powers only shows a small region of the moon with the star.   

Since the sun is not part of this event, no filters are needed.  The moon is dim enough to view Spica’s disappearance and reappearance with an optical assist without overpowering your vision with an afterimage, like that from a camera flash.

This is the seventh occultation in a series of 20 that runs through November 2025.  These events are not assigned to any single location, though they are progressively farther southward. This is the last Moon-Spica occultation visible from North America for this cycle of occultations. Next month’s stellar eclipse occurs over eastern Asia.

Here’s what to see:

Moon occults Spica
Chart Caption – 2024, November 27: Through a spotting scope, the moon begins to occult or eclipse the star Spica.

The bright edge of the morning crescent, known as the limb, slowly approaches Spica and covers it.  The moon continues its slow eastward sojourn with the star behind it and invisible until it reappears.

Moon occults Spica
Chart Caption – 2024, November 27: Through a spotting scope, Spica reappears at the moon’s night limb.

At the predicted reappearance time, look for Spica shining again at the night lunar limb.  Then the moon slowly separates from the star.

Earthshine

earthshine - Photo Caption - 2022, September 23: Crescent moon with earthshine.
Photo Caption – 2022, September 23: Crescent moon with earthshine.

The night portion is gently illuminated by earthshine, reflected sunlight from earth’s oceans, clouds, and land.

Occultation Timings

For those not living near the cities listed below, find the city listed in this link.  The times listed are in Universal Time (UT).  For locations in the Eastern Time Zone, subtract 5 hours; Central, 6 hours, Mountain, 7 hours.  The list has two sets of times.  The top list predicts the disappearance times and the second, the reappearance times. Countries are listed alphabetically with Canada near the top and the US at the bottom, including many locales.

Here are the predicted times for selected cities:

CityDisappears (a.m. Local Time)Reappears (a.m. Local Time)
Miami5:536:33
Atlanta5:356:37
New York City5:366:51
Detroit5:306:41
Chicago4:285:37
Minneapolis4:275:34
Dallas4:405:14
Albuquerque3:39 (Moon only 3° up)4:08
DenverStarts before moonrise4:21
Salt LakeStarts before moonrise4:18 reappears at moonrise

The starting times and ending times vary by longitude and where the sky watcher sees the star disappear behind the moon’s limb.

The full event is easily visible in the Eastern and Central Time zones.  The moon is in the process of the occultation in the Mountain zone.  It is not visible in the far western regions, but the moon appears near the star during morning twilight.

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