Dhanishta Navak is related to Hindu astrology especially the Nakshatras or birth stars. It is a period when some activities are not performed. It is mainly observed by certain Hindu communities in north and western parts of India
Dhanishta Navak is observed from the Dhanishta Nakshatra upto Rohini Nakshatra during the waning phase of moon or Krishna Paksha in Jyeshta month as per traditional calendar followed in North India . The corresponding period in Maharashtra, Andhra Pradesh, Gujarat and Karnataka is the Krishna Paksha of Vaishakh month.
The stars of Nakshatras that are part of Dhanishta Navak are Dhanishta, Satabhisha, Purva Bhadrapada, Uttara Bhadrapada, Revati, Ashvini, Bharani, Krittika and Rohini.
Some Hindu communities do not undertake any work related to home like repair or wood work etc.
There is also another inauspicious period related to Dhanishta and it is known as Dhanishta Panchak.