Chinese scientists and technicians have fixed a glitch in the recently launched Beidou (Big Dipper) experimental navigation satellite after 60 days of hard work, according to the Xi'an Satellite Control Center.

The control center reported that satellite number 4 is once again functioning normally.

The Beidou satellites provide all-weather and all-day navigation and positioning information.

Satellite 4, which went into orbit on February 3, was unable to deploy its solar panels correctly after launch, said an official with the control center.

China has put four Beidou (Big Dipper) experimental navigation satellites into orbit. The previous three were launched in 2000 and 2003.

Satellite number four serves as a backup satellite for the whole system and may some day replace Beidou 1, according to space officials.