@Shiva Tseba'oth said
"I was adopted when I was 3 months old and my documents indicate no hour of birth. I have been studying some astrology and, so knowing exactly when I was born is a must.
Is there a method to discover the time of birth?
I ask this because navigating the bureaucracy of my home country in search of that would be an enormous and probably useless task."
A competent Astrologer should be able to find the exact hour of birth in perhaps 80% of cases. It requires an accurate intuition and an ability to trace facts to their source. This method is called rectification. However, this sort of method is highly inaccurate these days owing to the lack of qualified astrologers. Obviously, anyone working in a Tropical system is going to go astray. The Sidereal practicioner is more of a rare breed, and among the minority who practice this method there are even fewer skilled at rectification.
Crowley, while lacking some of the technical elements of Astrology, was often able to deduce the Rising Sign by a person's appearance alone. This we can attribute to a superior intuition combined with a high degree of scientific accuracy.
Likewise, the trained Astrologer uses a variety of methods during Rectification:
First: physical characteristics. Most signs can be easily deduced by salient traits, such as facial forms and body shape, etc. (There is also a way to do this through palmistry, but that's a more complex issue.)
Second: empirical evidence. One checks to see if the Rising Sign lines up with the given timeframe. For instance: if one knows it was a night birth, this reduces the number of possible signs by half. There are many different ways to use this method.
Third: The history of the native. Every house rules a certain aspect of the native. An instance: We see that the native had an abusive father. We examine the various houses that might corroborate this. We see that Saturn is afflicted; to test this we place the Fourth house cusp at Capricorn (Ruled by Saturn) and check the Ascendant. This gives us Virgo Ascending. Does the native have keen features and a small frame? If so, we are one step closer to rectification.
See how the process works? It takes a lot of effort, but practice teaches. I've seen novice Astrologers pick up people's Rising Sign with uncanny accuracy. "Success is your proof."
So, in your case, let's examine the facts. You say you were adopted three months after your birth. You take this date and subtract the three months. This gives you the basic time frame. At this point we need to check different planetary positions based on your personality and physical characteristics. That gives us the day. Then we examine various Houses/Rising Signs to obtain the exact time.
Hope that was informative. If you want to post or PM me your info, I could give a more clear analysis of your situation.
As you Will,
93