The lunar Nodes, known as Rahu and Ketu in astrology, do their rounds in the twelve rasis of the zodiac, and complete one round of the zodiac, in about 18 years. Their movement, in contrast to the other planets, is in the reverse direction. In other words they will always be in retrograde motion. In this process they change their signs roughly, once in 18 months.
Previously, true Rahu and Ketu entered Virgo and Pisces respectively, on the 13th July 2014. Having stayed there for just over 18 months, they are now entering Leo and Aquarius respectively, on the 9th January 2016, where they are to remain in those signs till the third week of August 2017.
Lunar Nodes technically are not real planets. They are only the points of intersection of the orbit of the Moon with the ecliptic. Conventionally, only the mean positions of the nodes are taken to account by some section of astrologers for the panchanga calculations and predictive purposes, under the plea that there could be no true positions for imaginable points. However, as only the true positions for all the planets are taken for predictive and panchang purposes, scholars are of unanimous opinion that it will inconsistent to stick to any mean positions for the nodes alone.
Therefore as in the case of planets, where we are concerned only with their true or apparent positions, for the nodes also, only their true positions are taken for our evaluation. It must be noted while the motion of mean Rahu or Ketu will always be retrograde and uniform, the same of true nodes will not be so. It can be not uniform always. At times, the motion could become direct also. In the process, the true Rahu and Ketu can become static, for some days. The greatest difference between the true and mean positions of the nodes will be about 1.75 degrees. As for the mean nodes, the impending transits occur, on the 29th January 2016.