The planets are very powerful in nature and we all are under their influence. If these planets are weak or imbalanced they can make life miserable. In order to strengthen weak planets havan is performed. These Ashvath sticks are offered during fire ceremony (Havan), to pacify the ill effects of Guru or to strengthen the good effect of the planet.
Brihaspati is the Guru of Devas, personification of piety and religion, the chief offerer of prayers and sacrifices, represented as the Purohita of the gods with whom he intercedes for men. He is the Lord of planet Jupiter. He is often known simply as "Guru". According to Hindu scriptures, he is the guru of the Devas and the arch-nemesis of Shukracharya, the guru of the Danavas. He is also known Guru, the god of wisdom and eloquence, to whom various works are ascribed, such as the "atheistic" Barhaspatya sutras.
Guru is usually depicted with an elephant or chariot drawn by eight horses as his vehicle. He is also depicted in a lotus flower.He is described of yellow or golden colour and holding a stick, a lotus and his beads. He presides over 'Guru-var', Brihaspativar or Thursday.
He is of Sattva Guna and represents knowledge and teaching. His Tattva or element is Akasha or ether, and his direction is north-east. These sticks are offered to the fire by chanting shlokas which invariably end with a 'swahaa'.