The weird signs Haruhi made Kyon write
Tanabata (七夕, meaning "Evening of the seventh") is a Japanese holiday celebrated on the seventh day of the seventh month (July 7th) of the year. People would hang wishes written on strips of paper on bamboo trees, hoping the gods Orihime (織姫 Weaving Princess) and Hikoboshi (彦星 Male Star or Cow Herder Star) (represented by the stars Vega and Altair respectively) will grant them. Vega is 25 light years from Earth, and Altair is 16 light years.
Tanabata in the Haruhi Suzumiya Franchise[]
Haruhi Suzumiya believes the gods grant wishes, but the wishes travel to the gods at the speed of light, so it would take 16 years for one wish and 25 years for the other to be received. She believes the gods can grant wishes instantly once received, though, regardless of the speed of light.
Tanabata is an important event in The Melancholy of Haruhi Suzumiya series, for the main plot revolves around it. Monday, July 7, year -3, is when the main plot was formed. Kyon had first went back into that time with Mikuru Asahina on July 7, three years later, in Bamboo Leaf Rhapsody. Mikuru promptly fell asleep, while her adult version appeared and told Kyon to find Haruhi Suzumiya and assist her. Kyon found her at East Junior High. He claimed his name was "John Smith". Haruhi made Kyon draw weird signs on the quad; these were written as a message to the gods, Orihime and Hikoboshi and according to Yuki Nagato meant "I am here".
Asahina (small) had lost her TPDD, so she and Kyon went to see Nagato for assistance. She "froze" them in time for three years, releasing them on July 8th in their proper time.
Part of The Disappearance of Haruhi Suzumiya also takes place during this event. When Kyon activated the Emergency Escape Program, he was returned to that time. He met the adult version of Mikuru again, who told him to deliver another message to Haruhi shortly after their first parting. Afterward they met Nagato again, who revealed who the true culprit behind the incident was and what had to be done to stop them. Asahina (large) then took Kyon through time to December 18th in Kyon's regular time to restore the world-altering event.