On June 8, 2004 (April 21, 2004 in the lunar calendar), the phenomenon of "transit of Venus" occurred in my country. 2004 Transit of Venus On June 8, 2004, my country's "transit of Venus" began at 13:12 and ended at 19:18. This "rare astronomical phenomenon that is not seen in a century" lasted a total of 7.7 hours from the beginning to the end. June 06, 2012 The last "transit of Venus" in the 21st century. If you miss it, you will have to wait 105 years to observe visible "black drops" and "rings", and a rare astronomical phenomenon-the transit of Venus will occur in the sky. Zhao Junliang, former director of the Shanghai Observatory and honorary chairman of the Shanghai Astronomical Society, said at a lecture organized by the Shanghai Observatory that if this observation opportunity is missed, the next transit of Venus will wait until 2117. He also revealed that the principle of the transit of Venus can be used to find aliens.