Hare Krsna
The Herā-pañcamī festival takes place five days after the Ratha-yātrā festival. Lord Jagannātha has left His wife, the goddess of fortune, and gone to Vṛndāvana, which is the Guṇḍicā temple. Due to separation from the Lord, the goddess of fortune decides to come to see the Lord at Guṇḍicā. The coming of the goddess of fortune to Guṇḍicā is celebrated as Herā-pañcamī. Sometimes this is misspelled as Harā-pañcamī among the ativāḍīs. The word herā means “to see” and refers to the goddess of fortune going to see Lord Jagannātha. The word pañcamī means “the fifth day” and is used because this takes place on the fifth day of the moon.
(CC Madhya 14.107 purport)