I was born on the 25 of Tishrei 1981 at approx. 5:30 PM. According to most secular astrologers I am considered to be a Libra/Scorpio cusp sun sign (Oct. 19-25). Tishrei is considered the month of Libra according to Torah. Am I considered a Libra or a Scorpio? I seem to have some qualities of Libra and Scorpio both. How does Torah calculate astrological signs aside from months of the year? How do the calculations of Sign compare to those of secular astrology? Does the relationship between the moon and sun determine a change in my sign from year to year?
“Of the signs in heaven you shall have no fear.” (Jeremiah 10:2)
But this is what the Talmud says about your birth: (Friday 6th hour is Jupiter)
One who was born on the sixth day of the week will be a seeker. Rav Naḥman bar Yitzḥak said that this means that he will be one who seeks out mitzvot, as most of the activity on Friday involves preparation for Shabbat.
One who was born under the influence of Jupiter [tzedek] will be a just person [tzadkan]. Rav Naḥman bar Yitzḥak said: And just in this context means just in the performance of mitzvot.
See this letter from the Lubavitcher Rebbe on Astrology and Horoscope in Jewish Life for a beautiful explanation why even taking any interest is an issue.
Also see Rambam's Epistle to Yemen, Chapter 3, and his Commentary on the Mishnah, Avodah Zarah 4:7.