How and why did the moon get stained?

According to the 56th chapter of Dasham Skanda of Shrimad Bhagwat Purana, Lord Shri Krishna had darshan of the moon on the Chaturthi of Shukla Paksha of Bhadra month and he was accused of stealing Satrajit’s Samantak Mani.

To remove this stigma, he found the gem and returned the gem to Satrajit and removed the stigma. Ashamed, Satrajit then married his daughter Satyabhama to Lord Shri Krishna and also returned the gem to the Lord.

According to Shrimad Bhagwat Purana, if any person suddenly sees the moon on the day of Kalank Chauth, he becomes free from stigma by reading and narrating this story of Shrimad Bhagwat Puran.

The moon, endowed with 16 arts, became proud of its beauty. Once he mocked Lord Shri Ganesha after seeing his Gajmukh and Lambodar form, due to which Shri Ganesha got angry and got angry. He cursed the moon to be ugly and said that whoever looks at the moon from now on will surely be accused of falsehood.

Hearing this curse, Chandrama became sad and sat hiding. Then Lord Shri Narad ji thought that if the moon does not emerge, there will be hindrance in the creation cycle, then he advised the moon to worship Lord Shri Ganesh ji with the offering of laddus and malpuras.

Chandrama then pleased Lord Shri Ganesha by worshiping and praising him and prayed to free him from the curse. Lord Ganesha was pleased with his prayer and limited the curse by saying that whoever visits you on the Chaturthi of Bhadrapada month will definitely be tarnished.

For this reason, Chandra Darshan is not done on this Chaturthi. It is believed that those who regularly do moon darshan are protected from the inauspicious effects of moon darshan.