How to calculate the Rising sun ?

How to calculate the Rising sun (Ascendant) in your natal chart if the time of birth is not known?
I need only logical & analytical answers

u can use 12 NOON as the standard time if you're not sure of your birth time...www.alabe.com/freechart...

my lover is astrologer. he say his books say use noon if birth time not known.

Calculating the Rising Sign is an entirely different matter than casting a "sunrise" or "noon" chart -- both of these methods would render the chart as though you *were* born at sunrise or noon, and give an Asc based on that time, so if you do it this way, you'll just be analyzing someone else's Rising Sign. ;-)

There's a method known as "birth time rectification," which is used more frequently by Vedic (Jyotish) astrologers, but some western astrologers use it as well. The way they do this is by getting the dates of significant events in your life -- marriages, births, deaths, new jobs, relocations, illnesses -- various Big Dawg Life Occurrences -- and calculate the birth time based on that data.

You could check with a Vedic astrologer, or search for "birth time rectification" online to find out more, if you're interested. Such services do tend to be a bit on the expensive side, as a lot of work is involved for the astrologer. I'm not aware of any "cheap" methods, other than obtaining a copy of your birth certificate (assuming one with a time is available, as it would be in many countries).

All the best in your quest! :-)