Jyotish, Vedic Astrology, Longevity Computation.
Shukra can be placed to Surya during their retrogression. The other grahas (Mangal, Guru and Shani) are far from Surya during their retrogression. The key to understand this is the concept of superior and inferior conjunctions. Shatru Kshetra Harana When a Graha occupies its enemy sign, this Harana