Alaska is a state in the United States of America, in the extreme northwest portion of the North American continent. It is the largest U.S. state by area (by a substantial margin), and one of the wealthiest and most racially diverse.
The area that became Alaska was purchased from Russian interests on March 30, 1867. The land went through several administrative changes before becoming an organized territory in 1912 and the 49th state of the U.S. on January 3, 1959. The name "Alaska" is derived from the Aleut alaxsxaq, meaning "the mainland", or more literally "the object towards which the action of the sea is directed".
At the end of the Upper Paleolithic Period (around 12,000 BCE), Asiatic groups crossed the Bering Land Bridge into what is now western Alaska. At the time of European contact by the Russian explorers, the area was populated by Alaska Native groups.
The first European contact with Alaska occurred in the 1741, when Vitus Bering led an expedition for the Russian Navy aboard the St. Peter. After his crew returned to Russia bearing sea otter pelts judged to be the finest fur in the world, small associations of fur traders began to sail from the shores of Siberia towards the Aleutian islands. The first permanent European settlement was founded in 1784, and the Russian-American Company carried out expanded an colonization program during the early to mid-1800s. Despite these efforts, the Russians never fully colonized Alaska, and the colony was never very profitable. William H. Seward, the U.S. Secretary of State, engineered the Alaskan purchase in 1867 for $7.2 million.
In the 1890s, gold rushes in Alaska and the nearby Yukon Territory brought thousands of miners and settlers to Alaska. Alaska was granted territorial status in 1912.
During World War II, three of the outer Aleutian Islands—Attu, Agattu and Kiska—were the only part of the United States to have land occupied by the enemy during the war. The battle became a matter of national pride, defending the nation against the first foreign military campaign on U.S. soil since the War of 1812. The construction of military bases also contributed to the population growth of some Alaskan cities.
Alaska was granted statehood on January 3, 1959.
In 1964, the massive "Good Friday Earthquake" killed 131 people and leveled several villages.
The 1968 discovery of oil at Prudhoe Bay and the 1977 completion of the Trans-Alaska Pipeline led to an oil boom. In 1989, the Exxon Valdez hit a reef in the Prince William Sound, spilling between 11 and 35 million US gallons (42,000-130,000 m³) of crude oil over 1,100 miles (1,600 km) of coastline. Today, the battle between philosophies of development and conservation is seen in the contentious debate over oil drilling in the Arctic National Wildlife Refuge.
Kutup ışıkları, ya da aurora, genellikle kutup bölgelerinde görülen bir gece ışımasıdır. Aurora, gökyüzündeki doğal ışık görüntüleridir. Genelde gece görülen kutup ışıkları, çıplak gözle de izlenebilir. "Kuzey ışıkları" olarak da isimlendirilir. 
Çoğu kutup ışığı yüksek kuzey ve güney enlemlerinde görülür. Özellikle yay, bulut ve çizgi şeklinde oluşurlar. Bazıları hareket eder, parlaklaşır ya da aniden yanıp sönerler. Yeşil, auroraların en yaygın rengidir. Ancak çok yükseklerde olan kutup ışıkları kırmızı ya da pembe olabilirler. Çoğu aurora atmosferin 100 ile 1000 km aralığında oluşur. Bazıları atmosfer boyunca binlerce kilometre yatay uzunluğa sahip olabilir.  
Kutup ışıkları sıklıkla 11 yıllık güneş döngüsünün en yoğun zamanında görülür. Bu dönemde, güneş yüzeyindeki koyu lekeler sayıca artar. Güneşteki şiddetli patlamalar güneş lekeleriyle ilgilidir. Solar patlamalardan çıkan elektronlar ve protonlar, dünya atmosferiyle etkileşir. Bu etkileşim oldukça parlak auroralar yaratır. Bu aynı zamanda dünyanın manyetik alanında güçlü dalgalanmalar meydana getirir; (manyetik fırtına). Bu fırtınalar esnasında auroralar kutup bölgelerinden ekvatora doğru kayar. 
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