Tanabata

One of the five seasonal festivals

Tanabata, written with the characters for “seventh evening”, was one of the five seasonal festivals of the old calendar, held on the seventh day of the seventh month of the lunisolar year. It is a festival about the night sky.

A date that moved

When Japan adopted the solar calendar, many places simply kept the numbers, and Tanabata came to be held on 7 July. That moved it about a month earlier in the season — and 7 July usually falls before the rainy season has ended, a poor time for looking at stars.

Some places chose to keep the old season instead and hold the festival a month later. Sendai is the best-known example: its organisers say they use the calendar one month behind the current one, so the festival runs from 6 to 8 August, close to where the old date used to fall. The arcades of the city are hung with enormous, colourful paper streamers for the three days.

The traditional date

There is a third reckoning. Since 2001 the National Astronomical Observatory of Japan has published the traditional Tanabata date each year: the seventh day counted from the new moon that comes before the solar term Shosho. It falls somewhere between late July and late August and changes every year. If you want to see the sky the festival is about, that is the night to look up.