If you ask an Indian or Vedic priest what date it is, he may say something like this: 2071 Vikram Samvat (year number), Srāvana Māsa (lunar month), Jaya Samvatsar (year name based on 60-year cycle). There are many additional details such as Tithi (lunar day), Vārā (solar day), Paksha (lunar phase etc) but in this article we will only learn about how the year and the month are derived.
YEAR: In the year 57 BC, Vikrama Samvat era was founded by king Vikramāditya of Ujjain following his victory over the Sakas. King Vikramāditya’s life is also connected with the concept of Sādhe Sati but that is a topic for another article. So if we start Vedic calendar in 57 BC, then year 2014 in Gregorian calendar will translate to year 2071 (57 + 2014) in Vedic calendar. There are other Vedic systems for calculating year but Vikram Samvat is the most common.
MONTH: There are 12 rāśis (signs) and there are 12 lunar months. Names of each lunar month depends on two things: a) which signs the Sun transits through that month, b) which Nakshatrā (constellation) Full Moon takes place in during that month. For example, when Sun transits from Pisces into Aries, the name of that lunar month is known as Chaitra because the Full Moon during that month takes place in the Nakshatrā of Chaitra. Next, when Sun transits from Aries into Taurus, that lunar month is called Vaiśākha because Full Moon during that month takes place in Vishākhā Nakshatrā. And so on. There are some exceptions to this rule but in its simplest terms, this is how lunar months are derived.
12 Months in Lunar Calendar:
- Chaitra (Sun transits from Pisces to Aries, Full Moon in Chitrā)
- Vaiśākha (Sun transits from Aries to Taurus, Full Moon in Vishākhā)
- Jyeṣṭha (Sun transits from Taurus to Gemini, Full Moon in Jyeṣṭha)
- Āṣāḍha (Sun transits from Gemini to Cancer, Full Moon in Purva or Uttara Āṣāḍha)
- Śrāvaṇa (Sun transits from Cancer to Leo, Full Moon in Śrāvaṇa)
- Bhādrapada or simply Bhādra (Sun transits from Leo to Virgo, Full Moon in Purva or Uttara Bhādrapāda)
- Āśvina (Sun transits from Virgo to Libra, Full Moon in Āśvini)
- Kārtika (Sun transits from Libra to Scorpio, Full Moon in Kārttikā)
- Mārgaśīrṣa (Sun transits from Scorpio to Sagittarius, Full Moon in Mārgaśīrā)
- Pauśa (Sun transits from Sagittarius to Capricorn, Full Moon in Pushyā)
- Māgha (Sun transits from Capricorn to Aquarius, Full Moon in Māghā)
- Phālguna (Sun transits from Aquarius to Pisces, Full Moon in Purva or Uttara Phālguni)
Chart below shows each of the 12 Lunar months and corresponding months in Gregorian calendar (Source for diagram: http://hinduism.iskcon.org)