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How we know a birth time

A birth chart is only as good as the birth time behind it. On Stars at Birth, every celebrity chart shows where its time comes from and how reliable it is, using the Rodden rating, the standard scale astrologers have used since the 1980s.

Why the time matters

The Sun stays in a sign for about a month, so a date of birth is enough to know someone's Sun sign. The Moon changes sign every two to three days. The Rising sign changes about every two hours, and the houses with it. Get the time wrong by an hour and the Rising sign, the houses and much of the reading can change. That is why we only publish full charts for people whose birth time is on record. (If you don't know your own birth time, Atelier Holly has a guide to charts without a birth time.)

The Rodden ratings

The ratings were created by the American astrologer Lois Rodden to grade the reliability of birth data, and they are used by Astro-Databank, the largest public collection of famous people's birth data.

RatingWhere the time comes fromOn Stars at Birth
AAA birth certificate or official birth recordFull chart, Rising sign and houses
AThe person themselves, their family or someone close to themFull chart, Rising sign and houses
BA biography or autobiographyNot published as a chart for now
CNo known source, or a source that is not reliableSun sign lists only
DD"Dirty data": two or more conflicting timesSun sign lists only
XA date with no timeSun sign lists only

How we check every chart

  1. The rating. We look the person up by hand on Astro-Databank and take only AA or A data. We link to the entry from the chart, and we never copy its text.
  2. The cross-check. We check the date and place of birth against Wikipedia. If they disagree, we leave the person out.
  3. The calculation. We calculate the chart ourselves and compare the Sun, Moon and Ascendant with Astro-Databank's. They must agree to the minute of arc.

Every chart page shows the rating, the source and the date it was last checked.

Who we leave out, and why

Many very famous people have no reliable birth time. Some have several conflicting ones; others have none on record at all. We would rather leave someone out than publish a Rising sign we can't stand behind. You will find them on our Sun sign lists, which need only a date. We also leave out politicians and anyone under 18.

How the readings are written

Each reading is drafted with the help of AI from the chart and from the documented facts of the person's life, then checked by hand against the sources linked at the foot of the page. We don't invent quotes or events, and we don't make predictions about anyone's health or future. If you spot a mistake, please write to hello@atelierholly.com and we will put it right.