Rahu, the north or ascending node, is the point at which the Moon crosses the ecliptic to the north.

As the factors which determine eclipses, the nodes are the shadows of the Sun and Moon (speaking here symbolically, not astronomically). The north node, Rahu, is the shadow of the Moon, or the negative Moon. It has the power to obstruct, negate, cover or darken the Moon (the mind).

As the negative Moon, or the negative side of the Moon (the mind), Rahu represents illusion, hallucination, trance, psychosis, paranoia, and other such negative mental states.

The key to most nervous, psychological and emotional disturbances; susceptibility to drugs and psychic influences; mysterious diseases like cancer or neuro-muscular disorders; as well as most inexplicable general mental unhappiness, malaise and unrest in life, can usually be traced to the influence of these nodes, especially Rahu. This is particularly true when they combine with and augment the negative force of other malefics like Saturn.

Rahu has the power to overcome the Moon, and Ketu has the power to overcome the Sun. They can limit other planets as well, though not to such a degree. Similarly, Ketu can obstruct the Moon; it may create violent fantasies, an attraction to the lower or macabre side of life, drug addiction or alcoholism, or dark emotional states. Rahu can obstruct the Sun; it may create confused imagination, indecision, illusions about oneself and the capacity to lose oneself to collective or psychic influences. Yet Rahu is more dangerous to the Moon; and Ketu, to the Sun. As having the power to overcome the Sun, Ketu is the most powerful planet in the chart besides the Sun.

The positive influence of the nodes, however, is less common than the negative, and both tend to have a debasing effect upon us. Both nodes represent very difficult forces to handle, and their positive side may only come out through overcoming great obstacles in life and may have side-effects.

Rahu usually functions best when placed in a strong house, like the Ninth or the Tenth, with the ruler of that house powerfully placed elsewhere. There it can give fame, status and prestige. It may give this when strongly located in the First house also.

A strong Rahu gives worldly powers and success — the fulfillment of worldly desires, — but usually not inner fulfillment. It can give rise to worldly desires that can never be fulfilled, however successful the individual may be, resulting in outer success combined with inner turmoil.

In the spiritual realm, Rahu can give psychic powers and mediumship capacity, but also danger from drugs, danger of possession, and danger from black magic.