October 29 – November 1, 2021: The crescent moon moves in front of the stars of Leo in the eastern sky before sunrise. Watch the moon appear lower and the phase shrink (wane) each morning. Also note that there is no Full moon on Halloween this year!
by Jeffrey L. Hunt
As the month draws to a close, the moon appears to move in front of the stars of Leo. The moon is stepping toward its New moon phase and return to the evening sky.
As the moon displays its monthly set of moon phases, it appears farther eastward each night. The moon begins its moon phases as a thin crescent in the western sky. Each night it appears farther eastward with a thicker phase. When half-full, the First Quarter phase, the moon is in the southern sky at sunset. During the next week, the phase displays its growing gibbous phase. At the Full moon phase, it rises in the eastern sky at sunset and sets in the west near sunup.
After the full phase, the moon rises later and appears in the western sky during pre-dawn hours. At the second half-full phase, Last Quarter, the moon rises around midnight and it is in the southern sky near sunrise. The moon displays a thinning crescent as it rises closer to sunrise and continues to appear farther eastward. Finally, it disappears into bright morning twilight, only to reappear and start the progression again.
The complete cycle occurs during 29.5 days.
During late October, the moon is nearing its New moon phase. During these four mornings, it is lower in the eastern sky and thinner in phase.
Step outside an hour before sunrise. The constellation Leo is high in the eastern sky. Its backwards question mark of stars – known as the Sickle of Leo – stands highest. A triangle of stars – marking the haunches of the celestial Lion – is lower.
We see the westward-facing Lion in profile. Here’s what the moon is doing during these mornings.
October 29: The moon is in front of the stars of Cancer this morning, above Leo. The moon is 44% illuminated. It is between Pollux, in Gemini, and Regulus, the brightest star in Leo.
October 30: The crescent moon, 33% illuminated is over halfway up in the southeastern sky. It is 1.4° above Eta Leonis, in the Sickle of Leo.
October 31: One hour before sunrise, the moon, 25% illuminated, is nearly halfway up in the east-southeast, 5.9° to the upper right of Chertan – “the two small ribs” – in the haunches of Leo. Note that the moon is not at its Full moon phase. A Halloween Full moon occurs about once every 19 years. The next one in North America occurs in 2039.
November 1: The crescent moon – 15% illuminated – is about one-third of the way up in the southeast. The lunar slice is in Virgo, near the border with the Lion. The moon is 7.9° to the lower right of Denebola – “the tail of the lion.”
2021, October 29 – November 1: The thinning moon appears farther eastward near the stars of Leo.
December 30, 2021: As the year ends and the new one opens, the night sky’s brightest star – Sirius – is in the southern sky at the midnight hour.
December 31, 2021: This morning before sunup, the thin waning crescent moon appears near Mars and the star Antares. Four planets – Venus, Mercury, Saturn, and Jupiter – are on parade in the southwest after sundown.
December 30, 2021: The morning crescent moon seems to be captured in the Scorpion’s pincers to the upper right of Mars. Four Evening Planets – Venus, Mercury, Saturn, and Jupiter – are in the southwest after sundown.
December 28, 2021: The Great Andromeda Galaxy is nearly overhead at the end of the evening twilight.
December 29, 2021: The morning crescent moon approaches Scorpius and Mars. In the evening sky, four evening planets – Venus, Mercury, Saturn, and Jupiter – are lined up in the southwest. Venus is rapidly leaving the evening sky.