A North Korean satellite in orbit appears to be dead and no signal can be detected from the Kwangmyongsong-3 launched by Pyongyang in defiance of international sanctions.

US-based astrophysicist Jonathan McDowell of the Harvard-Smithsonian Center for Astrophysics said on Monday the satellite – believed to have been launched as a guise for banned missile tests – was clearly in orbit but was apparently not operating.

“To the best of our knowledge, the satellite isn’t operating,” McDowell told AFP. “It’s definitely up there and it’s whizzing around, but it’s just not feeling very well”.

The communist state successfully put the satellite, which it says is observing the Earth and airing patriotic songs, into orbit.

However, no songs can be heard, according to the center monitoring spaceflights. McDowell said it was unclear whether the satellite worked initially or it was transmitting at a level too faint for detection. The satellite is also not pointing down at the Earth as it should be, he added.

The satellite remains in orbit at least 505 kilometers (314 miles) above Earth even if it was not functioning.

Pyongyang launched the satellite with much fanfare on Wednesday, December 12, after it had claimed it was delaying the launch due to “technical flaws”. North Koreans celebrated as state-run Korean Central News Agency said the reclusive state had “successfully” put a satellite into orbit while its scientists said the technology was “flawless”.