Making sure a birth time is accurate is not always easy but master astrologer Donna Cunningham has the best advice about the issue that you'll find anywhere, so check out Donna's insights on her SkyWriter blog about this very basic astrological matter upon which all hinges!
For as you know, a person's, entity's, or event's birth time, or time of beginning, is part of the birth data astrologers consider before setting up or calculating a horoscope. Anything or anyone that has a beginning has a birth or natal chart, aka a radical or radix chart.
The hour and minute (and sometimes the second) are what produces the sign and degree rising on the horizon at that moment of beginning and thus the planets can be positioned in their proper places in the chart. Of course, date and place are the other requirements for setting up a chart and yes, some information can be gleaned without knowing an accurate time of entrance into the flux of time and space.
But that's like a photograph slightly out of focus...you need a correct time to view a precise picture of the planetary dynamics and their relationships (aspects) to one another. Years ago my own horoscope was out of focus since no birth time was recorded on my BC so I did an end-run by having my mother sign papers the hospital provided so I could get her hospital records of having me, and there it was - listed not once, but three times.
So the 12 'houses' in a chart are departments of life and knowing which house/s your Sun and Moon are in, as well as the other planets and points, is a surefire way to snag yourself a valuable horoscope that can be useful when looking at transits (where planets are now or whenever), Solar (or other planetary) Returns, and for progressing the chart to tell you an evolutionary tale of your life.
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