The sky on June 21, 1977 — 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 — 143.4° · sign Leo · constellation Leo
- ☿︎ Mercury — 79.8° · sign Gemini · constellation Taurus
- ♀︎ Venus — 44.4° · sign Taurus · constellation Aries
- ♂︎ Mars — 41.3° · sign Taurus · constellation Aries
- ♃︎ Jupiter — 77.6° · sign Gemini · constellation Taurus
- ♄︎ Saturn — 134.1° · sign Leo · constellation Cancer
- ☽︎ Moon 20% 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, 20% lit; the Moon was 392,422 km away.
astronomy-engine - How far Earth has travelled since [EXACT]
49.3 orbits of the Sun — 46,319 million km, that is 60,249 return trips to the Moon; 18,002 rotations of Earth; with the Sun — 357.7 billion km around the Galactic centre, 13.8 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 276 million km away; today it is 246 million km (closer by 1.1×).
astronomy-engine; checked against JPL Horizons for 2026-09-14 - Solar cycle [ESTIMATE]
That day fell in solar cycle 21, right at the minimum (12% through the cycle).
SILSO smoothed minima - When the sky repeats [EXACT]
Mars returns to that day’s point of its orbit on April 2, 2028; Jupiter — in 2036; 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 2,484″ 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.