The sky on July 13, 1987 — as it really was
That day the Sun stood in Gemini, while the horoscope says "Cancer". The gap is 23.7° of precession.
Bodies on the ecliptic (noon UTC)
- ☉︎ Sun — 110.6° · sign Cancer · constellation Gemini
- ☽︎ Moon — 324.1° · sign Aquarius · constellation Capricornus
- ☿︎ Mercury — 97.5° · sign Cancer · constellation Gemini
- ♀︎ Venus — 99.4° · sign Cancer · constellation Gemini
- ♂︎ Mars — 124.3° · sign Leo · constellation Cancer
- ♃︎ Jupiter — 27.5° · sign Aries · constellation Pisces
- ♄︎ Saturn — 255.6° · sign Sagittarius · constellation Ophiuchus
- ☽︎ Moon 92% 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, 92% lit; the Moon was 361,157 km away.
astronomy-engine - How far Earth has travelled since [EXACT]
39.2 orbits of the Sun — 36,866 million km, that is 47,953 return trips to the Moon; 14,328 rotations of Earth; with the Sun — 284.7 billion km around the Galactic centre, 11 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 392 million km away; today it is 245 million km (closer by 1.6×).
astronomy-engine; checked against JPL Horizons for 2026-09-14 - Solar cycle [ESTIMATE]
That day fell in solar cycle 22, right at the minimum (9% through the cycle).
SILSO smoothed minima - When the sky repeats [EXACT]
Mars returns to that day’s point of its orbit on January 11, 2027; Jupiter — in 2034.
sidereal periods: Mars 686.98 d, Jupiter 11.862 yr - How far the sky has drifted since [EXACT]
The vernal point has shifted 1,944″ since that day; the real constellations now sit 23.7° away from the astrologers’ “signs”.
precession 50.29″/yr
Other dates
Computed from the date only; nothing about you is stored.