Scorpio is the sign of the fall of the Moon because the depths of the natural 8th House of the zodiac are too much for the mind to take and it feels overwhelmed by these unfathomable wells of past Karma.
In this transit commencing on 18th July, 2013 the movement of the Moon also contributes to the shifting of the Jala Tattwa/ Water element-equally indicated by both the movement of Venus into Leo/ Śukra/ Shukra in Simha Rāśi/ Rashi and the Sun/ Ravi into Cancer/ Karkaṭa Rāśi/ Karkata Rashi-Venus being the Graha indicative of the Jala Tattwa and Karkaṭa Rāśi as well.
The mind will tend to view matters from a position of humility and surrender, from the depths where it surveys Kārmic/ Karmic realities as it were. The transit/ Gochara Chakra for the movement of the Moon through Scorpio/ Cañdra/ Chandra through Vṛṣcika Rāśi/ Vrishchika Rashi is given below-
Around noon on the 18th of July, 2013 the Moon would be very weak due to the transit of the junctional region between Libra and Scorpio. In addition the aspect of Rāhu/ Rahu now comes on the transit Moon. Death, transformation, doctors, astrologers, occultists and rites of passage will come to the fore. Research and oblique psychological pathways will appear. Secrecy and hidden motives may be paramount at this time and one ought to act accordingly.