Based on that assessment, the third stage of the rocket, as well as the satellite, would have entered orbit, aerospace experts said.
Though the Unha-3 rocket did not carry a warhead, it relied on technology similar to that of a long-range missile, leading Washington, Seoul and Tokyo to describe the launch as a de facto missile test that violated U.N. Security Council resolutions.
The North also said Wednesday that its launch was a success.
If North Korea indeed placed a satellite into orbit, it would mark a significant breakthrough in its decades-long attempt to develop an intercontinental ballistic missile capable of hitting the United States and would present a new threat for the Obama administration.
The North had carried out four previous missile or rocket launches, dating back to 1998. In the most recent one, eight months ago, the rocket broke apart after roughly 90 seconds and dropped into the sea.
The rocket launched Wednesday was fired from a facility in the country’s northwestern corner, not far from the Chinese border. It traveled southward, zipping over the water between South Korea and China, flying above the Japanese island of Okinawa, then heading toward the Philippines.
According to the Japanese government, stages of the rocket fell into the Yellow Sea and the East China Sea, the planned trajectory that North Korea had described in its report to the International Maritime Organization, which is responsible for maritime safety.
South Korean President Lee Myung-bak called an emergency security meeting, and a Japanese government spokesman called the launch “unacceptable.”
“It is extremely regrettable that North Korea went through with the launch despite our calls to exercise restraint,” said the spokesman, Osamu Fujimura.
China also expressed its unhappiness with the long-range launch. Foreign Ministry spokesman Hong Lei told reporters: “We express regret at (North Korea’s) launch in spite of the extensive concerns of the international community.”
Hong said China “believes U.N. Security Council reaction should be prudent and moderate and conducive to maintaining stability and avoiding escalation of the situation.”
In Washington, the White House called the launch a “highly provocative act that threatens regional security.”
Rep. Ileana Ros-Lehtinen (R-Fla.), chairman of the House Foreign Affairs Committee, criticized the launch, saying it shows that a defiant Pyongyang “is moving ever closer towards its ultimate goal of producing a nuclear ballistic missile.”
The launch caught North Korea’s neighbors off guard. Though the North had stated earlier this month that it would go ahead, South Korean military officials on Tuesday told reporters in Seoul that Pyongyang was disassembling its rocket to fix technical problems.