The sky on April 21, 1973 — 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 — 31.2° · sign Taurus · constellation Aries
- ☽︎ Moon — 254.8° · sign Sagittarius · constellation Ophiuchus
- ☿︎ Mercury — 6.1° · sign Aries · constellation Cetus
- ♀︎ Venus — 34.3° · sign Taurus · constellation Aries
- ♂︎ Mars — 318.2° · sign Aquarius · constellation Capricornus
- ♃︎ Jupiter — 309.8° · sign Aquarius · constellation Capricornus
- ♄︎ Saturn — 77.5° · sign Gemini · constellation Taurus
- ☽︎ Moon 86% 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 gibbous, 86% lit; the Moon was 404,969 km away.
astronomy-engine - How far Earth has travelled since [EXACT]
53.5 orbits of the Sun — 50,235 million km, that is 65,342 return trips to the Moon; 19,524 rotations of Earth; with the Sun — 388 billion km around the Galactic centre, 15 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 205 million km away; today it is 246 million km (farther by 1.2×).
astronomy-engine; checked against JPL Horizons for 2026-09-14 - Solar cycle [ESTIMATE]
That day fell in solar cycle 20, on the decline (75% through the cycle).
SILSO smoothed minima - When the sky repeats [EXACT]
Mars returns to that day’s point of its orbit on November 6, 2027; Jupiter — in 2032; 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 2,664″ 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.