Star birthday

The day each year on which your birth nakshatra — the Moon's star when you were born — comes round again in the solar month you were born in. Much of South India keeps this, not the Gregorian date, as the birthday: Janma Nakshatram in Tamil Nadu, Pirannal in Kerala.

The month is your solar month of birth, counted by your tradition's own solar calendar where it has one — Tamil, Malayalam, Punjab and Tulu each begin their months by their own rule — and otherwise by the Sun's sign. The day is the one in that month whose star at sunrise is your birth star.

Because the birthday is kept where you are. Whether your star holds at sunrise depends on when the Sun rises at your own place, so the same star can fall on different dates in Chennai and in New Jersey.

The place of birth is used only to work out your star and your birth month.

A solar month is 29 to 32 days and the Moon passes all 27 stars in about 27, so a star can come twice. Families differ on which day to keep, so both dates are shown rather than one chosen for you.

Yes — choose your star instead. The Moon crosses a whole star in about a day, so without a time the star cannot be worked out, but the month still comes from the date of birth.

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