Ada Lovelace

Mathematician · United Kingdom · 1815–1852

Sagittarius 17.6° · born December 10, 1815
Birth time unknown

Birth date sourced. Birth time unknown.Moon sign undetermined. The Moon crossed from Pisces into Aries during that day. Mercury crossed from Scorpio into Sagittarius during that day, so its sign is left open. Everything below uses only what the complete civil day settles.

The day, read honestly

Venus and Jupiter sit 0.7° from an exact conjunction — near enough that the tradition reads taste and expansion as a single working part. A conjunction is the least negotiable aspect in the scheme — no distance to argue across, so the pair arrives as a single instinct.

Positions at 12:00 civil time in London—a reference instant, not a birth time. No houses, rising sign, angles, or sect were computed.

Where the Sun actually stood

The Sun's exact place is 17.6° Sagittarius. That falls in the second decan, 10°–20°, sub-ruled by Mars in the classical scheme — a fire sign read through a mutable season.

The angles that hold

The tightest geometry in the chart puts Venus in the same degree of the zodiac from Jupiter, 0.7° off exact. Two bodies in the same degree are not read as neighbours but as a merger: whatever one wants, the other is already funding. Behind it, Saturn sextile Uranus at 0.8°, and Mars trine Neptune at 0.8° — both still well inside the orbs this site uses. Every angle named here holds for the whole of that day at the birthplace, so an unknown hour cannot take it away.

The classical map

Of the seven planets the classical scheme judges, three sit in a sign it has an opinion about. Venus in Scorpio at 1.5° is in detriment — the planet opposite its home, working against the grain; Mars in Aries at 20.4° is in domicile — the planet in its own sign, running on home rules; Saturn in Aquarius at 8.6° is in domicile. Dignity is a statement about conditions, not about worth.

The shape of the whole

Among the 8 placements whose signs hold for the whole day, the elements divide 4 fire, 3 water, 1 air; by modality, 4 mutable, 3 fixed, 1 cardinal. Fire weights a chart toward initiative — starting, asserting, spending energy to find out what happens. Mercury crossed from Scorpio into Sagittarius during that day, so its sign is left open. No settled placement falls in earth — an absence the tradition treats as information, not as a defect. Nothing was retrograde that day, which is less common than it sounds.

The Moon is genuinely open

The Moon crossed from Pisces into Aries during that day at the birthplace, travelling 12.1° between one midnight and the next. A birth time would settle it in a second; there isn’t one. So the Moon stays unnamed here — the alternative is a guess wearing the clothes of a fact.

Where this comes fromSources, revisions, and exactly what this chart assumes

Source article: Ada Lovelace · revision 1360639004
Wikidata: Q7259 · revision 2522257655
Retrieved: 2026-07-25T17:05:12.504Z
Birth date: 1815-12-10 · day precision · proleptic-gregorian
Birthplace: London, United Kingdom · Q84
Coordinates: 51.5072, -0.1275 · from London
Reference instant: 1815-12-10T12:01:15.000Z · noon civil time, not a birth time
Omitted: Rising sign, houses, angles, and sect—all require a birth time.
Unknown-time range: Moon travelled 12.13° · Moon sign undetermined. The Moon crossed from Pisces into Aries during that day.
Open signs: Mercury crossed from Scorpio into Sagittarius during that day, so its sign is left open.
Engine: astronomy-engine (repository dependency) · @zodiacs/engine/internal/math
Portrait: Antoine Claudet · public domain · Wikimedia Commons

Something wrong here?Ask us to correct or remove it.