Are there specific days to do Petra at night - Petra by Night ? How much does it cost?

Petra by night is  every Monday, Wednesday & Thursday, starting at 20:00, You can buy the ticket there for 17JD/P

Petra by night activity is arranged by a private company so you can do the visit as long as you purchased this activity ticket , and you don’t need to have Petra ticket at all ( Saying this, you just need Petra one day ticket for the main Petra tour same day or next day )