Field notes · UTC · approximate astronomy
December
2025 lunar calendar
A month-at-a-glance record of the Moon’s changing light and approximate tropical-zodiac position. Use it to observe a cycle—not to outsource a decision.
- 4
- principal phases
- 14
- sign changes
- UTC
- one declared clock
01 · Almanac
December 2025 at noon UTC
The daily phase, illumination, lunar day, and sign are noon snapshots. Marked times below are approximate UTC boundary estimates.
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Aries
Waxing Gibbous · 84%
Taurus
Waxing Gibbous · 91%
Gemini
Full Moon · 99%
Cancer
Full Moon · 98%
Leo
Waning Gibbous · 89%
Virgo
Waning Gibbous · 73%
Libra
Last Quarter · 41%
Scorpio
Waning Crescent · 22%
Sagittarius
New Moon · 3%
Capricorn
New Moon · 0%
Aquarius
Waxing Crescent · 13%
Pisces
Waxing Crescent · 30%
02 · Boundary ledger
When the month turns
Times are written in UTC so the reference stays reproducible. Your local calendar app may display them in your device time zone.
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01
Lunar phase
Full Moon
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02
Lunar phase
Last Quarter
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03
Lunar phase
New Moon
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04
Lunar phase
First Quarter
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05
Moon sign
Moon enters Taurus
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06
Moon sign
Moon enters Gemini
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07
Moon sign
Moon enters Cancer
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08
Moon sign
Moon enters Leo
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09
Moon sign
Moon enters Virgo
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10
Moon sign
Moon enters Libra
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11
Moon sign
Moon enters Scorpio
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12
Moon sign
Moon enters Sagittarius
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13
Moon sign
Moon enters Capricorn
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14
Moon sign
Moon enters Aquarius
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15
Moon sign
Moon enters Pisces
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16
Moon sign
Moon enters Aries
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17
Moon sign
Moon enters Taurus
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18
Moon sign
Moon enters Gemini
03 · Read the fine print
An honest compact calendar
Phase dates use a mean 29.530588853-day synodic cycle. Moon positions use a compact low-order geocentric longitude estimate sampled and refined in UTC. Dates and times are approximate; near a boundary, use a current high-precision ephemeris.
No planetary retrograde dates are shown because this dependency-free calendar does not have the high-precision planetary ephemeris required to publish them responsibly.
What the downloaded calendar contains
The .ics file contains only this month’s principal lunar phases and approximate Moon-sign changes. Each event repeats the approximation note. It contains no account, birth data, note, or tracking identifier.