The sky on December 21, 1971 — as it really was
That day the Sun stood in Sagittarius — sign and constellation agree here.
Bodies on the ecliptic (noon UTC)
- ☉︎ Sun — 269.0° · sign Sagittarius · constellation Sagittarius
- ☽︎ Moon — 313.6° · sign Aquarius · constellation Capricornus
- ☿︎ Mercury — 252.1° · sign Sagittarius · constellation Ophiuchus
- ♀︎ Venus — 297.8° · sign Capricorn · constellation Sagittarius
- ♂︎ Mars — 356.6° · sign Pisces · constellation Pisces
- ♃︎ Jupiter — 260.0° · sign Sagittarius · constellation Ophiuchus
- ♄︎ Saturn — 61.1° · sign Gemini · constellation Taurus
- ☽︎ Moon 14% 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, 14% lit; the Moon was 380,226 km away.
astronomy-engine - How far Earth has travelled since [EXACT]
54.8 orbits of the Sun — 51,488 million km, that is 66,972 return trips to the Moon; 20,011 rotations of Earth; with the Sun — 397.7 billion km around the Galactic centre, 15.4 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 166 million km away; today it is 246 million km (farther by 1.5×).
astronomy-engine; checked against JPL Horizons for 2026-09-14 - Solar cycle [ESTIMATE]
That day fell in solar cycle 20, on the decline (63% through the cycle).
SILSO smoothed minima - When the sky repeats [EXACT]
Mars returns to that day’s point of its orbit on May 24, 2028; Jupiter — in 2030; a full moon exactly on this date — December 20, 2029
sidereal periods: Mars 686.98 d, Jupiter 11.862 yr - How far the sky has drifted since [EXACT]
The vernal point has shifted 2,736″ 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.