Birthday signs · Aquarius season
What zodiac sign is January 31?
Under the tropical zodiac, January 31 is set in Aquarius. Each noon UTC on January 31 in the 101 years from 1930 through 2030 finds the Sun in Aquarius, at 10.41° to 11.9° Aquarius. Day 11 or 12 of Aquarius season is January 31, located in the middle part and associated with the element air.
Calculated across 1930–2030 · checked .
January 31 is Aquarius
| Aquarius at noon UTC | 101 of 101 years, 1930–2030 |
|---|---|
| Nearest change of sign | at least 10 days away |
| Birth time needed for the sign | no |
January 31 at a glance
| Sign | ♒︎ Aquarius, the Water-bearer |
|---|---|
| Element and mode | air, fixed |
| Polarity | positive (masculine) |
| Ruler | Saturn (traditional); Uranus (modern, 20th-century assignment) |
| Sun on this date | 10.4° to 11.9° Aquarius at noon UTC, 1930–2030 |
| Day of the season | day 11 or 12 of Aquarius season |
| Decan | second (10°–20°), face of Mercury |
| Sidereal sign (Lahiri) | Capricorn |
| Day number | 4 (modern numerology) |
Rulers: Ptolemy; modern list.6
The decan: middle Aquarius
| Noon Sun | 10.41° to 11.9° Aquarius |
|---|---|
| Decan | second (10°–20°) |
| Face ruler, Chaldean order | Mercury |
Faces after Lilly, in Chaldean order.3
January 31 by the numbers
| Day number | 4 (3 + 1 = 4) |
|---|---|
| Month-day number | 5 (1 + 4) |
| System | modern numerology, digit sums |
Digit sums as numerology guides give them.4
Where the date falls in the season
| Day of Aquarius season | 11 or 12 |
|---|---|
| Aquarius season opened | January 20 (48 years) or January 21 (53) |
| Aquarius season closed | February 17 (4 years) or February 18 (80) or February 19 (17) |
| Element and mode | air, fixed |
| Traditional ruler | Saturn |
Seasons by the noon-UTC rule; rulers after Ptolemy.2
Born at this point in Aquarius season
Born on January 31, in the middle of Aquarius, this person lands in a stretch of the season where the sign's cool curiosity starts to feel personal. They like to understand how groups work, yet they also keep a little distance so they can see the whole picture. At a dinner table or in a team meeting, they can step back, think it through, then return with an idea that changes the conversation. Their challenge is balancing a wish for freedom with a wish to be part of something.
Interpretation, not prediction.
The sidereal sign
| Sidereal sign, Lahiri ayanamsa | Capricorn, all 101 years |
|---|---|
| Noon Sun, sidereal Capricorn | 16.9°–18.3° |
| Convention | Indian (Vedic) astrology |
Ayanamsa convention.5
Born on January 31
- Tokugawa Ieyasu (1543–1616), founder and first shogun of the Tokugawa shogunate of Japan
- Franz Schubert (1797–1828), Austrian composer
- Alva Myrdal (1902–1986), Swedish sociologist and politician
- Rudolf Mössbauer (1929–2011), German nuclear physicist and Noble Prize in Physics
- Kenzaburō Ōe (1935–2023), Japanese writer and Nobel Laureate
- Beatrix of the Netherlands (1938), Queen of the Netherlands from 1980 to 2013
- Preity Zinta (1975), Indian actress
- Justin Timberlake (1981), American singer and actor
Birth dates checked on Wikidata.7
January 31 in history
Observed on this date:
- Amartithi (Meherabad, India, followers of Meher Baba)
- Independence Day (Nauru), celebrates independence from Australia in 1968.
- Street Children's Day (Austria)
Events on January 31:
- 1609: Wisselbank of Amsterdam established
- 1862: Alvan Graham Clark discovers the white dwarf star Sirius B, a companion of Sirius, through an 18.5-inch (47 cm) telescope now located at Northwestern University.
- 1961: Project Mercury: Mercury-Redstone 2: The chimpanzee Ham travels into outer space.
- 2007: Emergency officials in Boston mistakenly identify battery-powered LED placards depicting characters from Aqua Teen Hunger Force as Improvised explosive devices (IEDs), causing a panic.
- 2023: The last Boeing 747, the first wide-body airliner, is delivered to Atlas Air and operated for ApexLogistics. The aircraft was registered as N863GT and named "Empower".
How the answer was worked out
The tropical longitude of the Sun on January 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 January 31?
Among 101 sampled years from 1930 to 2030, January 31 is Aquarius in every case, counting the Sun at noon UTC.
Is January 31 on a zodiac cusp?
No. Between 1930 and 2030, the noon Sun stood in Aquarius on every January 31, and no January 31 lies within 10 days of a sign change.
What decan is January 31?
January 31 is found in the second decan of Aquarius (10°–20°) in every sampled year, and the corresponding Chaldean face ruler is Mercury.
What is the birthday number for January 31?
Modern numerology gives January 31 a day number of 4 and a month-day number of 5, 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 .
- Aquarius (astrology) — Wikipedia. Verified .
- Wikipedia: January 31 — Wikipedia (Wikimedia On this day feed); birth dates checked on Wikidata. Verified .