In the year 2016 Gopashtani is on Tuesday, 08.11.2016.
Important things about Gopashtami - According to Nirnayaamrit and Koorm Puran -
(1) Kartik Shukla Astami is known as Gopashtami.
(2) A cow is considered a sacred animal among the Hindu community. They call her mother.
(3) Cows were very dear to Lord Krishna.
(4) On Gopashtami the Hindus worship cows. It is believed that by worshiping cows, they get the blessings of cows. So they give cows bath ,decorate them with garlands,put a Tilak on their fore heads and worship them with Gandh and Pushpa , Parikrama is also taken around the cows. Along with the cows the cowherds are also worshiped.
(5) In the evening when the cows come back from the pasture, people welcome them, salute them, do Panchapochaar Puja and put the dust on their own fore head as a Tilak with the belief that these activities bring them prosperity.
(Ref. - Vrat Parichay. page 145)