What If You Don’t Know The Birth Time
A person’s birth date and birthplace allow astrologers to identify a specific configuration of the planets in the sky when the person was born. That’s useful information, but it isn’t enough. Knowing the exact time of birth moves that configuration around the birth chart wheel to the planets’ correct locations in the chart houses.
Here’s a simple diagram.
If you don’t know the time, most astrologers use noon on the birth day to plot a birth chart wheel. So, a planetary configuration at noon might look like this:
The correct birth time might move the configuration to look like this:
Not having the correct time, you’ll get a description of what the planets and zodiac signs mean, but the interpretation will be off as far as the specific areas of the person’s life where these planetary energies will play out.
Your best bet– get the exact time of birth if you can.
Second best– find out the approximate birth time.
Usually someone will remember that, for example, the birth was “in the late afternoon, just before rush hour;” or “around 10 in the morning;” or “in the middle of the night.” Any of those approximate times are better than no time at all.
Otherwise, noon on the birth day is used (which could be off by as much as 12 hours at either end of the day).
Even without the birth time, the chart report will be very useful. The Rising sign (Ascendant) may not be correct and the position of the Moon may be off a bit, but the rest of the planetary information will be accurate and very revealing.
Read The Importance of an Accurate Birth Time (and How to Get It) for more details.