How to calculate Arudha Lagna in astrology

(1) Count signs from the house of interest to the (2)sign containing its lord. Counting is in the zodiacal direction always. For example, if the house we are interested in is in Gemini and its lord Mercury is in Aquarius, we count signs from Gemini to Aquarius and get 9.
(3) Count the same number of signs from the sign containing the lord and (4)find the ending sign. In the above example, we count 9 signs from Aquarius and we end up in Libra.

Exception: Parasara's Rule
Parasara establishes that there are some exceptions from the above rule (fourth house rule).
Rule: if the lord of the house is in the 1st, 4th, 7th or 10th house, 4 houses must be deducted from the result.
• Saturn is in the Ascendant in Capricorn. So the 1st house Arudha (or Arudha Lagna) will not be Capricorn but Libra.
• 4th house Arudha for Cancer Ascendant and Venus in Aries: Cancer will be the Arudha and not Libra.

The Role of the Nodes
Rahu and Ketu play a special role in Jaimini astrology: they are co-lords of Aquarius (Rahu) and Scorpio (Ketu).
So Rahu must be taken as lord of Aquarius if Rahu is stronger than Saturn. Same for Ketu: Ketu is the lord of Scorpio if Ketu is stronger than Mars.

Arudha pada of a house is simply called arudha or pada also. We will denote the arudha pada on nth house with A n.
For example, arudha pada of 4th house is A4 and arudha pada of 9th house is A9.

Use of Arudha Lagna

While lagna stands for true self, arudha lagna (AL) stands for the maya associated with self. It shows the how the native is perceived in the material world. It shows the status of the native. A timid and confused individual may be perceived in the world as a strong leader. In that case, that is the maya associated with his personality and AL shows it.

Because arudha lagna deals with maya, illusions, perceptions and impressions, it is very important in judging various materialistic things. For example, Parasara and Jaimini taught that the 11th and 12th houses from AL show financial gains and expenditures. Natural malefics in the 3rd and 6th houses from AL show someone who is perceived as a bold person who hits enemies hard. Since such impressions are usually formed about materially successful people, malefics in the 3rd and 6th from AL make one bold and materially successful. Natural benefics in the 3rd and 6th houses from AL make one very gentle and restrained in public behavior. Such a person does not fight with others boldly. This combination is usually found in the charts of saints and saintly and mild-natured people.

The 10th house from lagna in D-10 shows one’s true conduct in society. It shows the one’s career and the true nature of one’s karma (work). The 10th house from AL in D-10 shows perceptions about one’s conduct in society. It deals more with one’s status in career.