■ Is Dokdo visible from the Oki Islands?
Although the oceans may look flat to the naked eye, we know that they are not. An approaching ship is visible from the mast down, slowly revealing its full shape. Through this simple fact, we know that the earth is round, not flat.
Dokdo is in the middle of the East Sea, between Ulleungdo and the Oki Islands. See the image below and determine whether Dokdo is visible from Ulleungdo and the Oki Islands.
The above image shows that Dokdo is visible from Ulleungdo at an elevation of 88 meters above sea level. The entire island is visible from an elevation of 524 meters. The highest peak on Ulleungdo is 984 meters above sea level, and the entire Dokdo is visible on a clear day. However, the Oki Islands are located 157.5 kilometers away from Dokdo, and its highest peak is 608 meters above sea level, which makes Dokdo not visible from the Oki Islands. Dokdo is only visible from a distance that is 106 kilometers closer to the island. It would have been difficult to locate an island sight unseen at a time when navigation techniques were underdeveloped.
1. Read the information above and determine which country was aware of Dokdo’s existence first.[Answer]
Teacher Notes
Verify whether Dokdo is visible from Ulleungdo and the Oki Islands through scientific methods. Japan claims that it was aware of Dokdo’s existence earlier than Koreans. A logical approach is necessary to refute these claims. The illustration in this chapter shows that Dokdo is visible from Ulleungdo but not from the Oki Islands. Confirm from previously presented material that people had been living in Ulleungdo since the Silla period. Therefore, it is reasonable to believe that inhabitants of Ulleungdo had been aware of Dokdo since the Silla period. Thus, the likelihood that Koreans were aware of Dokdo’s existence long before the Japanese is quite high. Logically, it is difficult to believe that Japan was aware of Dokdo’s existence before Koreans at a time when navigation techniques were underdeveloped.