One of the two non-physical channels of energy alongside the spinal column. The solar channel carries the "red" or warming energies of the vital body. In various traditions it is known as pingala, adam, od, rasana, and roma.
"When we are in the physical world, we must learn to be awake from moment to moment. We then live awakened and self-conscious from moment to moment in the internal worlds, both during the hours of the sleep of the physical body and also after death."