The five-day launch window for North Korea's Unha rocket opened Wednesday without any official sign of when the controversial mission will blast off, as neighboring countries stood on alert to track the launch.

Animation of the launch of North Korea's Unha rocket. Credit: Analytical Graphics Inc.

North Korea says the three-stage booster will soar into a near-polar orbit with an Earth observation satellite designed to monitor weather and natural resources.

North Korea says it scheduled the launch to commemorate the 100th birthday of Kim Il Sung, the communist state's 'eternal president' and founder.

Although the Unha rocket due to launch this week is not a weapon, officials in the United States, Japan and South Korea worry the test flight could demonstrate technology for North Korea's development of a long-range missile capable of delivering a nuclear bomb across a wide swath of the Asia-Pacific region, including parts of the United States.

The White House has warned of sharp consequences if the launch goes forward, including the suspension of planned shipments of food aid to North Korea's impoverished citizens.

The cube-shaped Kwangmyongsong 3 satellite and its 100-foot-tall Unha rocket were unveiled to Western media representatives this week. Kwangmyongsong means bright star in Korean, and Unha means galaxy.

North Korea claimed it installed the satellite into the nose of the Unha rocket in the last few days, but no images of the activity have been released.

CNN was one of several Western news organizations granted access to the North Korean launch site. Credit: CNN
 
Launching from a new rocket base on North Korea's west coast, the Unha booster will fly south, dropping its first stage in the Yellow Sea and its second stage in the ocean northeast of the Philippines.

Western reporters visited the Sohae Satellite Launching Station on Sunday, a rare gesture of transparency by the secretive North Korean regime. Also known as Tongchang-ri, the facility is located about 35 miles from the Chinese border city of Dandong.

The predicted launch trajectory will take the rocket just west of the South Korea coastline before flying over the Yellow Sea and East China Sea between Taiwan and Okinawa.

North Korea notified aviation authorities it could launch the rocket between 7 a.m. and 12 p.m. local time from Thursday until Monday. The window is open between 2200 GMT and 0300 GMT each day, according to notices to pilots and mariners.

The first day of the launch window passed with no liftoff. Weather may have prohibited launch Thursday, based on media reports.

About the size of a washing machine, the Kwangmyongsong 3 satellite will launch into a 300-mile-high orbit, according to North Korea. The craft weighs about 220 pounds.

North Korea claimed two previous rocket launches successfully placed satellites in orbit, but independent analysts confirmed nothing reached orbit on those missions.

This time, North Korean government officials gave Western media tours of the launch facility and control center ahead of the launch.