What a date genuinely fixes
The Sun moves a little under a degree a day, so a calendar date pins it closely. On 24 January it has been between about 3.4 and 4.7 degrees of Aquarius at noon in every year from 1930 to 2035, which is a spread of well under a degree and a half across more than a century.
That gives three things at once: a sign with no argument, a degree to within a degree and a half, and the decan that follows from it, the first band of Aquarius from zero to ten degrees, which the Chaldean order assigns to Venus. It is more than most sources offer and it is also where the date runs out.
It is also stable enough to be worth quoting. Because the leap year cycle keeps the calendar in step with the orbit, someone born on this date in 1941 and someone born in 2028 have Suns within a degree and a half of each other, which is a smaller gap than most people expect a century to allow.
The Moon needs the hour
The Moon covers around thirteen degrees a day and changes sign roughly every two and a half. On a given 24 January it can be in either of two signs, and in years where the change falls within the day itself the hour of birth decides which.
Across a run of years the same date has produced a Moon in every sign of the zodiac at one time or another. There is no lunar pattern attached to a calendar date, which is why no source publishes a moon sign table by birthday. It has to be computed.
The ascendant needs the place as well
The ascendant is the degree of the ecliptic rising over the eastern horizon, and the horizon sweeps the entire zodiac once a day. Two births six hours apart on the same 24 January will normally have ascendants a quarter of the wheel apart.
Latitude matters too, because signs rise unevenly and the distortion grows with distance from the equator. The same clock time gives different ascendants in Glasgow and in Quito. None of that can be inferred from the date, only from the hour and the birthplace, which is why the ascendant is the placement most often missing entirely.
House systems then disagree about what to do with it. Whole sign, equal house and Placidus all take the same ascendant and divide the chart differently, so the same planet can sit in different houses under each. That argument only begins once the hour is known, and without it there is nothing to argue about.
Where that leaves the reading
Once you have seen how much is still open, the standard Aquarius paragraph reads differently. It is a description of a month rather than a person, which is not a fault in the description, only in how it is presented.
The widget above takes your year, your birth time if you have it, and your birthplace, and returns the Sun's exact longitude with the measured distance to the nearest sign boundary. On this date that distance is comfortable, so the Sun holds even if the hour turns out to be wrong.
Questions people ask about this
Is a 24 January birthday always Aquarius?
Yes. The Sun enters Aquarius on 19, 20 or 21 January, so by the twenty fourth it is three to five degrees in and nothing about the hour or the time zone moves it back.
What is my moon sign if I was born on 24 January?
The date cannot say. The Moon changes sign every two and a half days, so it depends on your year and hour of birth and has to be calculated.
Can I find my rising sign from my birthday?
No. The ascendant depends on the clock time and the latitude of the birthplace, and it moves through all twelve signs in a day, so the date contributes nothing.
What can I get without a birth time?
The Sun and its decan, which are safe on this date, along with the slower planets. The Moon may be uncertain and the ascendant cannot be found at all.
What degree is the Sun on this date?
About three to five degrees of Aquarius, which places it in the first decan, the band assigned to Venus in the Chaldean order.
Why is the sun sign treated as the whole answer?
Because it is the only placement a date alone supplies. Everything else needs a year, an hour and a place, which a page written for a calendar date does not have.