There are five parts of Panchanga: Tithi, Var, Nakshatra, Yoga & Karan produces Panchanga together.
If Jataka was born on no moon day of Krushna Pakshas Chaturdashi or Prati Paksha of Shukla Paksha then Jatak suffer by Dosha. So, it is necessary to perform Shanti Puja by which you get release from Dosha.