The sky on April 21, 1971 — as it really was
That day the Sun stood in Aries, while the horoscope says "Taurus". The gap is 23.5° of precession.
Bodies on the ecliptic (noon UTC)
- ☉︎ Sun — 30.7° · sign Taurus · constellation Aries
- ☽︎ Moon — 339.6° · sign Pisces · constellation Aquarius
- ☿︎ Mercury — 28.2° · sign Aries · constellation Pisces
- ♀︎ Venus — 357.4° · sign Pisces · constellation Pisces
- ♂︎ Mars — 293.4° · sign Capricorn · constellation Sagittarius
- ♃︎ Jupiter — 245.2° · sign Sagittarius · constellation Scorpius
- ♄︎ Saturn — 52.6° · sign Taurus · constellation Taurus
- ☽︎ Moon 19% 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]
waning crescent, 19% lit; the Moon was 364,113 km away.
astronomy-engine - How far Earth has travelled since [EXACT]
55.5 orbits of the Sun — 52,116 million km, that is 67,789 return trips to the Moon; 20,255 rotations of Earth; with the Sun — 402.5 billion km around the Galactic centre, 15.5 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 148 million km away; today it is 246 million km (farther by 1.7×).
astronomy-engine; checked against JPL Horizons for 2026-09-14 - Solar cycle [ESTIMATE]
That day fell in solar cycle 20, near maximum (57% through the cycle).
SILSO smoothed minima - When the sky repeats [EXACT]
Mars returns to that day’s point of its orbit on September 23, 2027; Jupiter — in 2030; a full moon exactly on this date — April 20, 2027
sidereal periods: Mars 686.98 d, Jupiter 11.862 yr - How far the sky has drifted since [EXACT]
The vernal point has shifted 2,772″ since that day; the real constellations now sit 23.5° away from the astrologers’ “signs”.
precession 50.29″/yr
Other dates
Computed from the date only; nothing about you is stored.