As during the moon's circuit of the earth, the earth is also travelling
on its orbit, the moon will not be between the earth and the sun again
on completion of its orbit, but will have to traverse the further arc
shown in the figure to come between the earth and the sun. When the
moon has completed the circle of the ecliptic from the position ME,
its position relative to the earth has become as NF and it has not yet
come between the earth and the sun. Hence while the moon completes the
circuit of the ecliptic [216] in 27 days 8 hours, the time from one new
moon to another is 29 days 13 hours. Hence the nakshatras will not fall
on the same days in successive lunar months, and would not be suitable
as names for the days. It seems that, recognising this, the ancient
astronomers had to find other names. They had the lunar fortnights of
14 or 15 days from new to full and full to new moon. Hence apparently
they hit on the plan of dividing these into half and regulating the
influence which the sun, moon and planets were believed to exercise
over events in the world by allotting one day to each of them. They
knew of five planets besides the sun and moon, and by giving a day to
each of them the seven-day week was formed. The term planet signifies
a wanderer, and it thus perhaps seemed suitable that they should give
their names to the days which would revolve endlessly in a cycle,
as they themselves did in the heavens. The names of the days are:
Etwar or Raviwar. Sunday. (Ravi--the sun.)
Somwar. Monday. (Soma--the moon.)
Mangalwar. Tuesday. (Mangal or Bhauma--Mars.)
Budhwar. Wednesday. (Buddha--Mercury.)
Brihaspatwar or Guru. Thursday. (Brihaspat or Guru--Jupiter.)
Shukurwar. Friday. (Shukra--Venus.)
Saniwar or Sanichara. Saturday. (Sani--Saturn.)
The termination vara means a day. The weekdays were similarly named in
Rome and other countries speaking Aryan languages, and they are readily
recognised in French. In English three days are named after the sun,
moon and Saturn, but four, Tuesday, Wednesday, Thursday and Friday,
are called after Scandinavian deities, the last three being Woden or
Odin, Thor and Freya. I do not know whether these were identified with
the planets. It is supposed that the Hindus obtained the seven-day
week from the Greeks. [217]