The sky on December 18, 1971 — as it really was
That day the Sun stood in Sagittarius — sign and constellation agree here.
Bodies on the ecliptic (noon UTC)
- ☉︎ Sun — 265.9° · sign Sagittarius · constellation Sagittarius
- ☽︎ Moon — 274.2° · sign Capricorn · constellation Sagittarius
- ☿︎ Mercury — 253.6° · sign Sagittarius · constellation Ophiuchus
- ♀︎ Venus — 294.1° · sign Capricorn · constellation Sagittarius
- ♂︎ Mars — 354.7° · sign Pisces · constellation Pisces
- ♃︎ Jupiter — 259.3° · sign Sagittarius · constellation Ophiuchus
- ♄︎ Saturn — 61.3° · sign Gemini · constellation Taurus
- ☽︎ Moon 1% 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]
new moon, 1% lit; the Moon was 390,003 km away.
astronomy-engine - How far Earth has travelled since [EXACT]
54.8 orbits of the Sun — 51,500 million km, that is 66,987 return trips to the Moon; 20,015 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 162 million km away; today it is 244 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 21, 2028; Jupiter — in 2030; a full moon exactly on this date — December 17, 2051
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.