Japan: A tryst in the starry sky · Global Voices
Scilla Alecci

The artificial, dazzling lights of the metropolis often mask the stars above but it's worth looking at the vault of heaven on July 7 for this is the only night in the year when the two stars Vega and Altair, representing the two ill fated lovers, are destined to be reunited or so the legend foretells.
On the seventh day of the seventh lunar month  of the old calendar is the star festival, or Tanabata [en], in Japan, a magical event which has its roots  [en] in Chinese mythology.
Altair, on the night of Tanabata. By Scyllarides; CC license.
The legend tells, according to yuzenhosoi, ‘once upon a time'…
天の河の東に織り女という女性がいたそうです。彼女は天帝の娘でしたが、毎年毎年、機織の仕事に精を出して、雲の錦のような文様の美しい衣を織っていました。天帝は彼女が仕事に熱中して、いつまでも独身であることを哀れに思って、天の河の西にいる牽牛と結婚させました。ところが、お嫁にいってからは彼女は機織の仕事をやめてしまいました。天帝は彼女に腹を立てて、天の河の東側に戻らせてしまいました。そして毎年一度だけ、七月七日の夜に、天の河を渡って牽牛と逢うことになりました。
The reunion of the two lovers, Orihime the celestial weaver and Hikoboshi, the cowherd, is every year subject to the will of the God of Heaven, Noriko explains.
この日に雨がふると天の川があふれて、ふたりは会うことができません。
日本で７月初旬の降水確率は５３％。
さて今年ふたりはめでたく会えるでしょうか？
In Japan in early July there is generally a 53 percent chance of rain. So, will they be able to happily meet this year?
For those who share concerns with the blogger above, Goodchoice indicates an easy way to find the two stars in the night sky.
晴れた夏の夜（20～21時ごろを目安に）に東の空を眺めると、ひときわ明るい星が3 つ、三角形に並んでいるのがわかります。これがいわゆる夏の大三角形で、北にある星がこと座のベガ、東にあるのがわし座のアルタイル、西にあるの がはくちょう座のデネブです。[…]
ベガとアルタイルの間には、光の帯、天の川が流れていますが、その光がとても淡く、残念ながら山奥など真っ暗な場所でしか見られません。
Deneb Altair e Vega. By Air Force One, CC license.
During the weeks ahead of Tanabata, small trees of bamboo adorned with pieces of colored paper may be seen on the  corners of the streets, outside shops and supermarkets and in some nearby shrines.
It is a tradition to write a wish on the strip of paper (短冊, tanzaku) and tie it to a branch of such a  tree.
These and other decorations that symbolize the two lovers, like petite paper kimonos and nets or lucky symbols like cranes, are then burned on the night of July 7, with the hope that those wishes may be realized.
Tanabata decorations in Sendai. By Noriko Minaki
Takechan on his blog made a digital version of the Tanabata strips of papers and proposes a questionnaire.
七夕短冊～願いが叶うとしたら？あなたの願いは何ですか？