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Birth time unknown: what can still be computed

The short answer: most of it. The long one is below, with an exact list of what disappears and why substituting noon is worse than leaving a blank.

The same date, computed twice

The same date computed twice. Exactly what depends on the Earth’s rotation disappears — and nothing beyond that.

Three things disappear, and all three have one origin: they depend not on where the bodies are in their orbits but on how far the Earth has turned. Without a time, nobody knows that.

What stays correct

• The signs of all ten bodies. In a day the Sun moves about a degree, Venus and Mercury under two. So the sign is almost always the same at midnight and at noon.
• Every angle between bodies. Aspects barely change in a day, so that whole section of the chart is complete.
• Retrograde motion. A planet does not turn around mid-day.
• The Moon’s phase. It changes slowly and does not depend on the hour.

The one exception is the Moon. It crosses a sign in two and a half days — about thirteen degrees a day. If you were born on a day it changed sign, without a time it cannot be settled. The site says so in that case rather than picking one of the two.

Why not just substitute noon

Because noon produces an ascendant. A specific one, with a degree, which will look exactly as convincing as a real one — and will be invented with a probability of roughly eleven in twelve.

And it gets worse: the ascendant drags all twelve houses with it. One substituted number makes an entire column of the chart invented — and precisely the column that answers “in which area of life”. A blank is more honest here, and it is the only thing that does not mislead.

So it appears nowhere on this site: with no time, the houses column shows a dash, and the reading says plainly that it is shorter.

Where to find the time if you want it

• The birth certificate. In many countries the time is recorded on it. It is the only reliable source.
• The hospital’s records. Often kept longer than people assume, and released on request.
• Family memory — carefully. “Some time around dawn” usually means a window of about three hours. Not hopeless (see below), but not a time.

If you know a range

The most useful trick for “somewhere between seven and ten”: compute the chart twice, at the start and at the end of the range. If the ascendant lands in the same sign both times, you never needed the precision and can use the chart as complete.

If it lands in different ones, you at least know which two options the choice is between and can read both. That is more honest than getting one and not knowing it was chosen by a coin.

How it looks in the reading itself

In practice: a reading without a time is about a quarter shorter, and exactly one kind of sentence disappears — the kind that begins with “in which area of life”. Instead of “Venus in the seventh house” you get “Venus in Taurus”, and the second statement is no less true, just less specific.

What is not damaged at all is the theme you asked about. The site takes it not only from the house but from the sign’s ruler and from the aspects, and those do not depend on the time. So the relationships reading works without a birth time: the seventh house drops out, Venus, Mars and the angles to them stay.

And separately: we have not written “this reading is incomplete” in small print at the bottom anywhere. If the time is missing, it is said in the text itself, at the point where the house would have been mentioned.

And what about rectification

Sooner or later you will meet an offer to “recover” your birth time from life events: an astrologer asks about moves, marriages and losses, finds a time at which the transits to those dates look convincing, and calls it yours. This is called rectification.

We do not do it and do not plan to. The reason is simple: a fitted time looks exactly like a real one — degree, houses, everything. But it was fitted to your answers, not measured. After that you read a chart built on an assumption, and nothing in it reminds you of that.

This is not an accusation against the people who practise it: within the tradition the technique is old and coherent. It simply contradicts the one rule this site rests on — every number must be computed, not fitted.

What to do now

Compute the chart without a time — the field is optional. Nine rows out of ten will be correct, every aspect will be there, and that is enough to tell whether you want to go further. More on what the time buys you in the article on the ascendant.

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