The sky on June 21, 1973 — as it really was
That day the Sun stood in Gemini — sign and constellation agree here.
Bodies on the ecliptic (noon UTC)
- ☉︎ Sun — 90.0° · sign Gemini · constellation Gemini
- ☽︎ Moon — 332.3° · sign Pisces · constellation Aquarius
- ☿︎ Mercury — 115.0° · sign Cancer · constellation Gemini
- ♀︎ Venus — 109.2° · sign Cancer · constellation Gemini
- ♂︎ Mars — 0.4° · sign Aries · constellation Pisces
- ♃︎ Jupiter — 311.4° · sign Aquarius · constellation Capricornus
- ♄︎ Saturn — 84.9° · sign Gemini · constellation Taurus
- ☽︎ Moon 73% 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, 73% lit; the Moon was 394,451 km away.
astronomy-engine - How far Earth has travelled since [EXACT]
53.3 orbits of the Sun — 50,078 million km, that is 65,138 return trips to the Moon; 19,463 rotations of Earth; with the Sun — 386.8 billion km around the Galactic centre, 14.9 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 143 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, on the decline (76% through the cycle).
SILSO smoothed minima - When the sky repeats [EXACT]
Mars returns to that day’s point of its orbit on January 6, 2028; Jupiter — in 2032; a full moon exactly on this date — June 20, 2035
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.