Arundhati, wife of Sage Vasishta, is famous for her chastity, piety and single-minded devotion for her husband. Due to her devoutness and faithfulness, she became a star in the sky known as Arundhati Nakshatra. Arundhati was the daughter of Kardama Prajapati and Devahuti. Mahabharata mentions that there is no one as devout and faithful as Arundhati.
There are many instances in the Puranas when Arundhati rescued people with the power of her chastity and faithfulness.
Legend has it that once there was intense drought on earth. Saptarishis who were residing in the Himalayas also were troubled by the famine created by the drought. Arundhati then performed intense Tapas and pleased Shiva and was able to bring rain on earth.
This act earned her the praise of Saptarishis and Devas.
Arundhati left her physical body on earth while performing Tapas on the banks of holy Saraswati River.
Arundhati Nakshatra is located near the Saptarishi Nakshatras. She resides near Vasishta Nakshatra.
It is a practice among certain Hindu communities for the groom to show Arundati Nakshatra to the newly wed bride.
Another belief is that those people who are nearing their death cannot witness Arundathi Nakshatra. It is also believed that if a person is able to witness the Nakshatra then death will not approach him for next six months.