Dhanurmasa, is an important period in traditional Hindu calendar. The month is known as Dhanur Maas as the sun transits through the Dhanur Rashi (Sagitarius) and the period ends with the Makar Sankranti. In some regions the first day of Dhanur Maas is known as Dhanur Sankranti. In 2009, Dhanur Masa begins on December 16 and ends on January 14, 2010.

The month Dhanurmasa, is of great spiritual significance. The period when the sun starts moving northward from the Topic of Capricorn to the Tropic of Cancer is called uttaraayana. The opposite period when the sun moves southward is called dakshinaayana. According to our shastras, one human year corresponds to one day for the celestials; uttaraayana is their daytime and dakshinaayana the night.

Once, on the eve of dakshiNaayaNa, the celestials assembled on the peaks of Mountain Meru and prayed to the Upendra form of Lord ViShNu. When the Lord arrived, the celestials told Him that their “night” was approaching and sought His permission to go to their respective abodes. Then Ratri devi, the patron deity of night and dakshiNaayaNa, took on the form of a beautiful damsel and prostrated before the Lord. She pleaded with Him as follows “Lord, everybody views dakshiNaayaNa as a bad time. Nobody performs any good deeds in that period. I am universally reviled. I will undertake penance to obtain your grace. If I do not achieve my goal, I will commit suicide and end this life of infamy”. The assembled celestials concurred and pleaded her case before the Lord. The merciful Lord took pity on her and blessed her as follows, “Ratri devi, your duration consists of 3 seasons of 2 months each. Out of these, the first two seasons shall be deemed to dear to me. Within these 2 seasons consisting of four months, there shall be a hierarchy in which kartIka shall be the dearest, followed by AshvIja, Bhadrapada and finally shravana. All pious and meritorious acts performed in these four months shall yield immense benefits. Due to this, people will now look forward to this time of the year, thus removing the stigma attached to you”. From then on, these fours months became special in the Hindu calendar.

The last portion of the night i.e., the one-and-half hours before sunrise, has been given a very special status by our shastras. They decree that this is the best time for humans to wake up and start performing their prescribed religious activities like sandhyavandane, chanting of mantras etc. The beginning of this period is called ‘brahmi muhurta’. The same injunctions hold true for the nighttime of the celestials also. Here, their special time starts upto the end of dakshiNaayaNa. This period is called ‘dhanur maasa’ and roughly corresponds to the time when the Sun transits the zodiac sign of Dhanus or Sagittarius. It is said that the celestials wake up at this time and perform special prayers to the Lord. Our shastras decree that during dhanur maasa, humans too should wake up at the brahmI muhurta and perform puja to the Lord. People following these injunctions will be specially blessed with health, wealth, happiness and the good fortune. It should be remembered that puja to the Lord should be performed every single day during the dhanur maasa.

Dhanurmasa is also called as Shoonya Masa because it is considered as inauspicious to do any good things other than Godly functions. This month is allotted to Gods and for us it is a blank – meaning Shoonya. Lord Krishna declares in the Bhagavad Gita: “I manifest the most in the month of Margashira ( Dhanurmasa – Dec. 16 to Jan. 14) among the months of a year.” This highlights the religious significance of Dhanurmasa in the Hindu calendar. For this reason, sages have set apart this month to be completely focused on devotional activities. Other non-devotional social activities (such as weddings) are prohibited during this month so that attention can be given exclusively to the worship of God without any diversions.

It is said that Lord Shree Krishna had gone to Gurudev Sandipani Rushi's hermitage for education in this month. So, on this account, devotees dress-up God in outfits of a student and offer breakfast very early before God goes to school. Even Lunch box (Tiffin box) is given to God while going to school.