Bhaadrapada sukla panchami is called as Rishi panchami,which comes on the next day of Ganesha chaturthi. On this day, people worship Saptarishies along with Arundathi and performs vratha. Sapta maharishies are Rishi Kasyapa, Rishi Atri, Rishi Bharadwaja, Rishi Viswamitra, Rishi Gowtama, Rishi Jamadagni, Rishi Vasishta. Arundathi is wife of Rishi Vasishta.
According to Vrathakalpa, once upon a time, a king named Sitaswa asked Lord Brahma about a vratha which relieves the sins of women immediately. Then Lord Brahma told about this vratha. In Bhavishyottara purana also, Lord Krishna told about this vratha mahtya, vratha vidhana to king Dharmaraja. So, it is mainly a vratha of women to get rid off their sins.
1.On the afternoon of this day, go to near by pond or river, brush the teeth with bark of uttareni plant and do bath.
2.Make a wish to perform this vratha. Then do puja to Lord Ganesha.
3.Do puja to uttareni plant(Achyranthes aspara), then pluck it off, do brush once again with its bark.
4.Married women do head bath by applying oil to body and wear kumkum, chandan. Widows do bath wear bhasma.
5.Come to home, make a stage or mandapa in puja room of the house. Place kalasa on that mandapa.
6.First do puja to Yamuna river then to Saptamaharushies and Arundathi.
7.Lighten deepa with four wicks, maintain it throughout puja.
8.Imagine that Saptamaharishies and Arundathi are blessing you from the sky, during puja time.
9.Offer naivedya with curd, Bengal gram, Amaranthus.
10.After completing puja, take prasada.
According to Vajrotsava chandrika, women who performs this Vratha will get more love and affection from their husbands and Widows will get longliving husband in next janma. It also free the sins of women due to mistakes happened during their menstrual periods. So, Every women should perform this Vratha even once in their lifetime.