I am come back

在西元1974年地球向m13星團發射阿雷西博密碼，這是一個人類訊息的名片， 過了27年之後在2001意外得到了外星人的回應， 祂們以麥田圈的形式同樣用阿雷西博密碼排列出屬於他們的訊息。 回想過去多數古文明裡的壁畫或者陶器都有祂們的足跡，他們是不是即將回來了呢?
In 1974, the Earth launched the Arecibo code
In 1974, the Earth launched the Arecibo code to the m13 cluster,
as a business card for the human message.
Surprisingly, after 27 years the earth received the respond from aliens
using the Arecibo code to convey their messages in the form of crop circles. Looking back to most of the ancient civilizations,
many of them had traces on their frescoes or pottery that doesn't belong to earth,
Are they coming back now?