The Fifteen Days of Miracles—from the first day of the Tibetan new year (Losar, February 12) until the fifteenth (February 27)—commemorate the special time when Guru Shakyamuni Buddha showed miraculous powers in order to subdue six tirthika, or non-Buddhist teachers, who lacked faith in him, and to inspire more faith in his followers. It culminates on the full moon, the fifteenth day of the lunar calendar, which is the actual day of Chotrul Duchen.
Losar is traditionally celebrated for three days, during which Tibetans spend time with friends and family, eat, play games, and relax. A number of rituals and customs have developed around it, such as the eating of a special soup called “guthug” on the 29th day of the last Tibetan month of the year, two days before Losar. In the monasteries, there is a Losar tradition to do the extensive Palden Lhamo puja before dawn.
The Fifteen Days of Miracles are also a time for pilgrimage and intensive Dharma practice.