Birthday signs · Capricorn season
What zodiac sign is December 31?
Under the tropical zodiac, December 31 is set in Capricorn. Each noon UTC on December 31 in the 101 years from 1930 through 2030 finds the Sun in Capricorn, at 8.85° to 10.34° Capricorn. Day 9 to 11 of Capricorn season is December 31, located in the early part and associated with the element earth.
Calculated across 1930–2030 · checked .
December 31 is Capricorn
| Capricorn at noon UTC | 101 of 101 years, 1930–2030 |
|---|---|
| Nearest change of sign | at least 8 days away |
| Birth time needed for the sign | no |
December 31 at a glance
| Sign | ♑︎ Capricorn, the Goat |
|---|---|
| Element and mode | earth, cardinal |
| Polarity | negative (feminine) |
| Ruler | Saturn (traditional) |
| Sun on this date | 8.9° to 10.3° Capricorn at noon UTC, 1930–2030 |
| Day of the season | day 9 to 11 of Capricorn season |
| Decan | first (86 years) and second (15); faces: Jupiter, Mars |
| Sidereal sign (Lahiri) | Sagittarius |
| Day number | 4 (modern numerology) |
Rulers: Ptolemy; modern list.6
The decan: early Capricorn
| Noon Sun | 8.85° to 10.34° Capricorn |
|---|---|
| Decans | first in 86 years, second in 15 |
| Decan line crossed | 10° |
| Face rulers, Chaldean order | Jupiter, Mars |
Faces after Lilly, in Chaldean order.3
December 31 by the numbers
| Day number | 4 (3 + 1 = 4) |
|---|---|
| Month-day number | 7 (3 + 4) |
| System | modern numerology, digit sums |
Digit sums as numerology guides give them.4
Where the date falls in the season
| Day of Capricorn season | 9 to 11 |
|---|---|
| Capricorn season opened | December 21 (5 years) or December 22 (82) or December 23 (14) |
| Capricorn season closed | January 19 (49 years) or January 20 (52) |
| Element and mode | earth, cardinal |
| Traditional ruler | Saturn |
Seasons by the noon-UTC rule; rulers after Ptolemy.2
Born at this point in Capricorn season
Born on the final stretch of the Capricorn season, this person stands right at the edge where one year gives way to the next. The sign values duty, planning, and steady effort, and those habits are fully formed by now. Even so, the closing degrees carry a restless pull toward what comes after. This person sorts through what the year brought, deciding what to keep and what to set down, and that sorting can feel heavier than it looks from outside.
Interpretation, not prediction.
The sidereal sign
| Sidereal sign, Lahiri ayanamsa | Sagittarius, all 101 years |
|---|---|
| Noon Sun, sidereal Sagittarius | 15.3°–16.7° |
| Convention | Indian (Vedic) astrology |
Ayanamsa convention.5
Born on December 31
- Jacques Cartier (1491–1557), Breton maritime explorer of North America
- Andreas Vesalius (1514–1564), Flemish anatomist, physician and author
- Henri Matisse (1869–1954), French artist
- George C. Marshall (1880–1959), American army officer and statesman
- Simon Wiesenthal (1908–2005), Jewish Austrian Holocaust survivor and Nazi hunter
- Alex Ferguson (1941), Scottish association football manager and former player
- Alex Salmond (1954–2024), Alba Party leader and First Minister of Scotland 2007–2014
- Val Kilmer (1959–2025), American actor
Birth dates checked on Wikidata.7
December 31 in history
Observed on this date:
- International Solidarity Day of Azerbaijanis (Azerbaijan)
- First Night (United States)
- Last Day of the Year or Bisperás ng Bagong Taón, special holiday between Rizal Day and New Year's Day (Philippines)
- Novy God Eve (Russia)
- Ōmisoka (Japan)
- The first day of Hogmanay or "Auld Year's Night" (Scotland)
- The seventh of the Twelve Days of Christmas (Western Christianity)
- The sixth and penultimate day of Kwanzaa (United States)
Events on December 31:
- 535: Byzantine general Belisarius completes the conquest of Sicily, defeating the Gothic garrison of Palermo (Panormos), and ending his consulship for the year.
- 1790: Efimeris, the oldest Greek newspaper of which issues have survived till today, is published for the first time.
- 1956: The Romanian Television network begins its first broadcast in Bucharest.
- 1995: The final comic of Calvin and Hobbes is published.
- 2011: NASA succeeds in putting the first of two Gravity Recovery and Interior Laboratory satellites in orbit around the Moon.
How the answer was worked out
The tropical longitude of the Sun on December 31 was calculated at noon UTC for every year from 1930 through 2030 by Astronomy Engine, with each year's sign read from it.1 How the Machine works
Questions people also ask
What zodiac sign is December 31?
Among 101 sampled years from 1930 to 2030, December 31 is Capricorn in every case, counting the Sun at noon UTC.
Is December 31 on a zodiac cusp?
No. Between 1930 and 2030, the noon Sun stood in Capricorn on every December 31, and no December 31 lies within 8 days of a sign change.
What decan is December 31?
Two decans of Capricorn contain December 31: the first, the face of Jupiter, holds 86 sampled years, and the second, the face of Mars, holds 15.
What is the birthday number for December 31?
Modern numerology gives December 31 a day number of 4 and a month-day number of 7, found by summing the digits.
Sources
- Astronomy Engine JavaScript reference — Don Cross, Astronomy Engine. Verified .
- Ptolemy, Tetrabiblos, Book I — LacusCurtius, University of Chicago. Verified .
- Decan (astrology): the faces of the planets (after Lilly) — Wikipedia. Verified .
- Life Path Number — Numerology.com (practitioner site). Verified .
- Ayanamsa (Lahiri and other sidereal conventions) — Wikipedia. Verified .
- Capricorn (astrology) — Wikipedia. Verified .
- Wikipedia: December 31 — Wikipedia (Wikimedia On this day feed); birth dates checked on Wikidata. Verified .