Diwali, New Moon, Solar Eclipse - Transforming darkness into light

Deepawali or Diwali is certainly the biggest and the brightest of all Hindu festivals. It's the festival of lights (deep = light and avali = a row i.e., a row of lights) that's marked by four days of celebration, which literally illumines the country with its brilliance, and dazzles all with its joy. Each of the four days in the festival of Diwali is separated by a different tradition, but what remains true and constant is the celebration of life, its enjoyment and goodness.
Historically, the origin ofDiwali can be traced back to ancient India, when it was probably an important harvest festival. However, there are various legends pointing to the origin of Diwali or 'Deepawali.' Some believe it to be the celebration of the marriage of Lakshmi with Lord Vishnu. Whereas in Bengal the festival is dedicated to the worship of Mother Kali, the dark goddess of strength. Lord Ganesha, the elephant-headed God, the symbol of auspiciousness and wisdom, is also worshiped in most Hindu homes on this day. In Jainism, Deepawali has an added significance to the great event of Lord Mahavira attaining the eternal bliss of nirvana. Diwali also commemorates the return of Lord Rama along with Sita and Lakshman from his fourteen year long exile and vanquishing the demon-king Ravana. In joyous celebration of the return of their king, the people of Ayodhya, the Capital of Rama, illuminated the kingdom with earthen diyas (oil lamps) and burst crackers.

From Darkness Unto Light...

In each legend, myth and story of Deepawali lies the significance of the victory of good over evil; and it is with each Deepawali and the lights that illuminate our homes and hearts, that this simple truth finds new reason and hope. From darkness unto light — the light that empowers us to commit ourselves to good deeds, that which brings us closer to divinity. During Diwali, lights illuminate every corner of India and the scent of incense sticks hangs in the air, mingled with the sounds of fire-crackers, joy, togetherness and hope. Diwali iscelebrated around the globe. Outside India, it is more than a Hindu festival, it's a celebration of South-Asian identities. If you are away from the sights and sounds of Diwali, light a diya, sit quietly, shut your eyes, withdraw the senses, concentrate on this supreme light and illuminate the soul.

http://hinduism.about.com/od/diwalifestivaloflights/a/diwali.htm