The sky on May 21, 1931 — as it really was
That day the Sun stood in Taurus — sign and constellation agree here.
Bodies on the ecliptic (noon UTC)
- ☉︎ Sun — 59.5° · sign Taurus · constellation Taurus
- ☽︎ Moon — 106.6° · sign Cancer · constellation Gemini
- ☿︎ Mercury — 35.9° · sign Taurus · constellation Aries
- ♀︎ Venus — 30.5° · sign Taurus · constellation Pisces
- ♂︎ Mars — 139.8° · sign Leo · constellation Leo
- ♃︎ Jupiter — 108.2° · sign Cancer · constellation Gemini
- ♄︎ Saturn — 293.0° · sign Capricorn · constellation Sagittarius
- ☽︎ Moon 16% illuminated
astronomy-engine ephemerides (VSOP87/ELP), IAU 1930 constellation boundaries. Positions accurate to a fraction of a degree.
The day’s dossier, from real data
Checkable facts with a tag and a source; the classical reading is in the chart.
- The Moon that day [EXACT]
waxing crescent, 16% lit; the Moon was 378,847 km away.
astronomy-engine - How far Earth has travelled since [EXACT]
95.4 orbits of the Sun — 89,631 million km, that is 116,586 return trips to the Moon; 34,835 rotations of Earth; with the Sun — 692.2 billion km around the Galactic centre, 26.7 light-days.
29.78 km/s along the orbit; 230 km/s around the Galactic centre - Mars then and now [EXACT]
On that day Mars was 223 million km away; today it is 245 million km (farther by 1.1×).
astronomy-engine; checked against JPL Horizons for 2026-09-14 - When the sky repeats [EXACT]
Mars returns to that day’s point of its orbit on April 23, 2027; Jupiter — in 2038.
sidereal periods: Mars 686.98 d, Jupiter 11.862 yr - How far the sky has drifted since [EXACT]
The vernal point has shifted 4,788″ since that day; the real constellations now sit 22.9° away from the astrologers’ “signs”.
precession 50.29″/yr
Other dates
Computed from the date only; nothing about you is stored.