BEIJING -- China's first lunar probe, Chang'e I, will reach the moon's orbit Monday morning and currently, it was traveling on the expected trajectory, scientists said Sunday.

Chang'e I, following the instructions of the Beijing Aerospace Control Center (BACC), will carry out its first braking at perilune at about 11:00 am Monday to slow down, so that it can be captured by the lunar gravity and become a circumlunar satellite, said Wang Yejun, chief engineer of BACC.

"The speed of Chang'e I can reach 2.4 km per second when it arrives at perilune, and it will likely fly away from the moon if the braking is not conducted in time," Wang said.

"The first braking at perilune is another key moment in the long journey of Chang'e I," he said.

China's first lunar probe, Chang'e I, named after a legendary Chinese goddess who flew to the moon, blasted off on a Long March 3A carrier rocket on October 24 from the Xichang Satellite Launch Center in southwestern Sichuan Province.