The Moon can be in either of two signs, sometimes three
The Moon travels about thirteen degrees a day, so it clears a sign roughly every two and a quarter days. Any given 5 October therefore contains either one boundary crossing or none, and a birth in the morning can have the Moon in a different sign from a birth that evening. Nothing about the date narrows this down.
That matters because readings load a great deal onto the Moon. It is the placement associated with habit, response and what a person reaches for without deciding to, and it changes faster than anything else in the chart. Two people who share this birthday and were told the same thing about being Libra may have Moons with nothing in common.
The rising sign is completely undetermined
The ascendant is the point of the zodiac coming over the eastern horizon at the moment of birth, and the whole circle passes over it in a day. On 5 October, as on every date, all twelve signs take their turn. Only the hour and the geographic latitude of the birthplace fix which one was up.
This is the placement that decides the house framework, meaning which area of life each planet is read as belonging to. A Sun at twelve degrees of Libra falls in the tenth house for one person born on this date and in the fourth for another, and those readings barely resemble each other. If a birth time is genuinely unavailable, the rising sign calculator without a birth time will at least show which signs remain possible.
What the date does fix
The solar degree, and tightly. Across more than a century the noon position on this date varies by about one and a third degrees, held there by the leap year correction that keeps the calendar in step with the orbit. That is close enough to treat the birthday as a genuine coordinate rather than an approximate label.
It also fixes the decan. Twelve degrees of Libra falls in the second of the sign's three ten degree bands, which the Chaldean scheme assigns to Saturn beneath the Venus rulership of the sign itself. Tradition reads that middle band as the more measured and exacting stretch of Libra, where the sign's weighing habit has an edge of standard to it rather than simple accommodation.
Why the sun sign is the least personal part
Roughly one person in twelve shares your sun sign, and everyone born within a day or so of you shares your solar degree as well. It is the placement that varies least between people and the one that popular writing has made carry the most weight, which is a poor match.
The chart as a whole is a set of positions at a single moment from a single place, and most of it moves too quickly to be recovered from a date alone. Libra is a true statement about a 5 October birth. It is also the least distinguishing thing that can be said about one, and the parts that would distinguish it are exactly the parts a calendar cannot hold. The degree and the decan take the answer a little further, and after that the hour and the birthplace have to do the work.
Questions people ask about this
What sign is 5 October?
Libra in every year checked from 1930 to 2035. The date sits about twelve degrees into the sign, far enough from both boundaries that neither the hour nor the birthplace can move it.
Can I work out my Moon sign from the date alone?
No. The Moon changes sign every two and a bit days, so a single date usually allows two possibilities and occasionally three. The hour and the year are both needed to settle it.
How much does the rising sign change the reading?
Considerably, because it sets which house each planet occupies. The same planetary positions read through a different ascendant produce a different chart, which is why the birth time matters more than the birth date for most of the detail.
What decan does this birthday fall in?
The second decan of Libra, ten to twenty degrees. Its Chaldean sub ruler is Saturn, applied over Venus as the ruler of the whole sign, and readings treat that as a shift of emphasis rather than a change of sign.
Does everyone born on 5 October share a degree?
Within a fraction of a degree, yes, and across a century within about one and a third. The Sun is the slowest changing personal placement, which is exactly why it is also the least individual one.
What should I do if I have no birth time?
Use noon as a default and treat the Moon and the ascendant as open questions. On this date the sun sign is unaffected, so the missing time costs you the fast placements rather than the headline one.