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 Palash sticks are offered during fire ceremony (Havan), to pacify the ill effects of Chandra or to strengthen the good effect of the planet.
Chandra is a lunar deity. Chandra (moon) is also known as Soma and identified with the Vedic Lunar deity Soma. He is described as young, beautiful, fair; two-armed and having in his hands a club and a lotus. He rides his chariot (the moon) across the sky every night, pulled by ten white horses or an antelope. He is connected with dew, and as such, is one of the gods of fertility. He is also called Nishadipati (Nisha=night; Adipathi=Lord) and Kshuparaka (one who illuminates the night). He as Soma, presides over Somvar or Monday.
He is of Sattva Guna and represents the Mind, the Queen or Mother.