Sun sign boundary
Taurus-Gemini cusp
Your Sun is in Taurus before it reaches 0° Gemini, and in Gemini from that boundary onward. The birth year and moment decide which sign applies.
Check the transition for your birth year
Choose a year from 1900 to 2026. No birth details are saved by this lookup.
Approximate universal times for the Sun entering Gemini. The highlighted row is your selected year.
| Year | Date | Time · UT |
|---|---|---|
| 2021 | 2021-05-20 | ≈ 19:37 |
| 2022, selected year | 2022-05-21 | ≈ 01:23 |
| 2023 | 2023-05-21 | ≈ 07:09 |
Times are rounded estimates, not exact birth cutoffs. Your local clock can show a different time or date. Use the calculator for time-zone conversion and births close to the boundary.
Calculate my birth chartContinuity and variety
Taurus uses a fixed earth style: continuity and tangible value give the Sun's purpose a focus. Gemini uses mutable air: comparing ideas and changing approaches become the focus. The boundary changes the Sun's sign, while the rest of the chart still needs its own reading.
Taurus
Earth · Fixed
Traditional ruler: Venus
Read Sun in TaurusGemini
Air · Mutable
Traditional ruler: Mercury
Read Sun in GeminiTwo sign themes can come from different planets
A hypothetical Taurus Sun with Mercury in Gemini can combine sustained purpose with a flexible way of discussing it. The conversational theme comes from Mercury. It does not require treating the Sun as two signs.
Read the Sun as the purpose or identity theme, Mercury as thought and communication, and Venus as appreciation and relating. Each placement contributes something specific.
An unknown time can leave the sign unresolved
If the Sun crosses this boundary during the possible birth period, both signs remain possible. Astriel keeps that uncertainty visible instead of substituting a noon chart.
Choose an approximate interval or unknown time in the calculator. The birthplace supplies the historical time zone. A single local calendar date can include times on both sides of the transition.
A house cusp is a separate question
These dates concern the Sun's zodiac sign. In Placidus, Astriel's default, house membership follows calculated cusp degrees. A sign change does not automatically change the Sun's house.
Read the Placidus house guideCalculation, precision and sources
The table uses the same apparent geocentric tropical Sun positions as Astriel's chart engine. Times use Astronomy Engine 2.1.19 and its Espenak-Meeus conversion between universal and terrestrial time.
Universal time follows Earth's rotation; modern UTC is the civil clock standard kept close to it. Historical dates before 1962 use universal time rather than a UTC clock that did not yet exist.
Independent checks against NASA/JPL covered twelve transitions in each of six sample years. Position and time-scale differences remain, so minute display is not a one-minute accuracy guarantee. Future birth years are excluded.
Interpretations follow the owner-supplied astrology reference, sign boundaries and sign classifications. The planetary example is hypothetical. No personality trait is established by an astronomical degree.
Astriel's methods and limits · NASA/JPL coordinate and time-scale documentation