Sun-based Upagrahas
Five upagrahas called Dhuma, Vyatipaata, Parivesha, Indrachaapa and Upaketu are defined based on Sun's longitude. The exact formulas are given in Table 6. All these upagrahas are very malefic in nature. Any houses occupied by them in rasi chart or divisional charts are spoiled by them.
Table 6: Sun-based Upagrahas
Upagraha Longitude Formula
Dhuma Sun's longitude + 13320'
Vyatipaata 360º – Dhuma’s longitude
Parivesha Vyatipata's longitude + 180
Indrachaapa 360º – Parivesha’s longitude
Upaketu Indrachaapa’s longitude + 1640'= Sun's longitude – 30
It may be noted that Dhuma and Indrachaapa are apart by 180 and Vyatipaata and Parivesha are apart by 180.
Other Upagrahas
Six upagrahas called Kaala, Mrityu, Arthaprahaara, Yamaghantaka, Gulika and Maandi are more difficult to compute. Kaala is a malefic upagraha similar to Sun. Mrityu is a malefic upagraha similar to Mars. Arthaprahaara is similar to Mercury. Yamaghantaka is similar to Jupiter. Gulika and Maandi are similar to Saturn.
A day starts at the time of sunrise and ends at the time of sunset. A night starts at the time of sunset and ends at the time of next day’s sunrise. Depending on whether one is born during the day or the night, we divide the length of the day/night into 8 equal parts.
Daytime births: The first part is ruled by the lord of weekday and then we cover planets in the order of weekdays. The part after the one ruled by Saturn is lord-less. After that, Sun’s part comes. For example, the first 1/8th of the daytime on a Thursday is ruled by Jupiter. Next part is ruled by Venus. The 3rd part is ruled by Saturn. The 4th part is lord-less. The 5th part is ruled by Sun. The 6th part is ruled by Moon. The 7th planet is ruled by Mars. The 8th part is ruled by Mercury.
Table 7: Ruling planets
Rulers of the 8 parts of the DAY
Weekday 1st 2nd 3rd 4th 5th 6th 7th 8th
Sun Sun Moon Mars Merc Jup Ven Sat —
Mon Moon Mars Merc Jup Ven Sat — Sun
Tue Mars Merc Jup Ven Sat — Sun Moon
Wed Merc Jup Ven Sat — Sun Moon Mars
Thu Jup Ven Sat — Sun Moon Mars Merc
Fri Ven Sat — Sun Moon Mars Merc Jup
Sat Sat — Sun Moon Mars Merc Jup Ven
Rulers of the 8 parts of the NIGHT
Weekday 1st 2nd 3rd 4th 5th 6th 7th 8th
Sun Jup Ven Sat — Sun Moon Mars Merc
Mon Ven Sat — Sun Moon Mars Merc Jup
Tue Sat — Sun Moon Mars Merc Jup Ven
Wed Sun Moon Mars Merc Jup Ven Sat —
Thu Moon Mars Merc Jup Ven Sat — Sun
Fri Mars Merc Jup Ven Sat — Sun Moon
Sat Merc Jup Ven Sat — Sun Moon Mars
Night time births: The first part is ruled by the 5th planet from the lord of weekday and then we cover planets in the order of weekdays. For example, the first 1/8th of a Thursday night is ruled by the 5th planet from Jupiter, i.e. Moon (Jupiter, Venus, Saturn, Sun, Moon – that’s the 5th one). Next part is ruled by Mars. The 3rd part is ruled by Mercury. The 4th part is ruled by Jupiter. The 5th part is ruled by Venus. The 6th part is ruled by Saturn. The 7th planet is lord-less. The 8th part is ruled by Sun.
Table 7 gives the list of the ruling planets of all the eight parts of the daytime and night time on all weekdays.
Once we divide the day/night of birth into 8 equal parts and identify the ruling planets of the 8 parts, we can find the longitudes of Kaala etc upagrahas using the following procedure:
(1) Kaala rises at the middle of Sun’s part. In other words, we find the time at the middle of Sun’s part and find lagna rising then. That gives Kaala’s longitude.
(1) Mrityu rises at the middle of Mars’s part.
(1) Artha Praharaka rises at the middle of Mercury’s part.
(1) Yama Ghantaka rises at the middle of Jupiter’s part.
(1) Gulika rises at the middle of Saturn’s part.
(1) Maandi rises at the beginning of Saturn’s part.
Suppose one is born on Thursday night and we want Yamaghantaka’s longitude in his chart. Suppose night starts at 6 pm and ends at 6 am on the next day. We see from the table that Jupiter rules the 4th part of a Thursday night. Each part is 12/8 = 1.5 hours. The 4th part starts 4.5 hours after sunset, i.e. at 10:30 pm, and ends 1.5 hours later. So Jupiter’s part extends from 10:30 pm to midnight. The middle point of this part is at 11:15 pm. We find lagna rising at 11:15 pm and that will be Yama Ghantaka’s longitude.