Shadow planets Rahu and Ketu are ever retrograde in their motion. Forever chasing Sun and Moon in order that they might avenge their separation by Sun and Moon after the Churning of the Ocean. With such action, they cause the eclipse of Sun and Moon. As planets, they move through the birth chart and gochara (transit) in backwards - retrograde - moving motion and every 18 months, change signs and their all - important Rahu-Ketu Axis, which has significance for nations and their leadership in particular. They also elicit, by their transit and retrograde motion, changes within the human person. Rahu and Ketu affect all with their transits. During June of 2014, Rahu and Ketu will change signs (peyarchi).
Read more 
