What is jaimini astrology : Arudha pada, upapada and chara karkas

The ancient Sanskrit text called Jaimini Sutras, attributed to MaharishiJaimini, who was a disciple of Rishi Vyasa, son of Parashara. Jaimini Sutras arranged in four chapters cover Karakamsa, Arudha, Upapada and navamsa in the first chapter; Longevity, Diseases, Profession, Progeny and Spouse, in the second; Longevity, Nature and cause of death, in the third; and in the fourth chapter it covers the account of pre-natal epoch.

The Jaimini System of prognostication is distinctly different from the Parashari System, the basic differences being with regard to aspect, determination of Karakas, Badhaka bhavas and the Dashas. In Jaimini System aspect has been assigned to the Rasis or signs which are synonymous with Bhavas or Houses, the Karakas are fixed according to longitudes gained by planets in particular signs, the Dashas are assigned to signs, and the method of determination of Badhakas is far more complicated, and its prediction-method based on Padas is also different.

Arudha Padas
Arudha Padas are one of the most important features in Jaimini astrology. Each house of a chart has its Arudha Lagna, which gives another point of detailed view of that house.
Special Arudhas are
• The Arudha of the 1st house is called Arudha Lagna.
• The Arudha of the 12th house is Upapada Lagna.

HOW TO CALCULATE ARUDHA LAGNA

Chara Karakas
Jaimini astrology defines the Chara Karakas. These Karakas depend on the planetary positions in the horoscope.
In Prashari Astrology the Sun, apart from being karka for father, is Atmakarka for each and every horoscope but according to Jaimini the Sun may be Atmakarka in one horoscope but in the next horoscope the Sun may become Daiv karka or any other amongst the list. Hence each and every karka is changeable from horoscope to horoscope. With the following sutras the sage defines the variable Karkas and he starts with Atmakarka.
A planet with highest degrees without considering sign is known as Atmakarka. Here the sage is strict on choosing the seven karakas from seven planets i.e. from Sun to Saturn.
Planet with second highest degrees is Amatyakarka and
similarly with decreasing longitude comes
Bharatrikarka
Matrikarka
Putrakarka
Gnatikarka
Darakarka.
Atmakarka is the supreme lord of the planets. If a benefic planet becomes Atmakarka and it is completely free from malefic influences and well placed in the horoscope, it is capable of final alancipation of soul or the Moksha.