“Wait. What?” you may be asking. “How can Alaska have both the easternmost and westernmost points in the United States?” In short, it has to do with hemispheres and the 180th Meridian.
In case you need a quick refresher on some long forgotten earth science, the Prime Meridian is the line of longitude defined as zero. Imagine the earth as a ball with a rubber band stretched around it evenly from top to bottom. The rubber band represents the great circle that divides the earth running north to south. That circle is the Prime Meridian on one side (0o) and the 180th Meridian (180o) on the other side. Together, they define the eastern and western hemispheres. The U.S falls almost completely in the Western Hemisphere.
Alaska’s Aleutian Islands arc right up to the edge of the Western Hemisphere at the 180th Meridian making Amatignak Island (179o West), Alaska the westernmost point in the U.S. Longitudinally, Alaska also has the easternmost point, Semisopochnoi Island (179o East), as the Aleutian Islands cross the 180º Meridian, into the Eastern Hemisphere. That makes Alaska the most northern, western and eastern state, longitudinally, in the U.S.
In real terms, the westernmost U.S. island is Attu Island at 172o East. Attu is nearly 1,100 miles from mainland Alaska and 750 miles northeast of the Japanese Kurile Islands. Attu was the site of the only land battle of World War II fought on incorporated territory of the United States and took place in May 1943. The island has been uninhabited since 2010.
When you register to give blood with Community Blood Center this summer, now through September 3, 2016, you will be automatically entered to win an Alaskan Adventure for Two. To learn more, visit GivingBlood.org.