BEIJING - China's first lunar probe, Chang'e-1, which entered the moon's orbit Monday morning, still has to undergo three key steps before it can really start its moon probe mission, a deputy chief commander of China's lunar obiter project said here Monday.

The three steps include two brakings at perilune, three-dimensional positioning of the satellite, and the adjustment of the working model of the satellite's sub-systems, Long Jiang, deputy chief commander of the lunar obiter project, told a press conference.

The satellite, which successfully completed its first braking at perilune and became China's first circumlunar satellite Monday morning, will perform its second braking at about 11:00 a.m. Tuesday and third one at around 8:00 a.m. Wednesday, according to Pei Zhaoyu, spokesman with the China National Space Administration (CNSA).

"The lunar probe will enter its final orbit after completing the next two brakings, which is significant for the lunar exploration project," Long said.

He said the satellite still has to implement complicated three-dimensional positioning after entering the final orbit.

"The instruments on the satellite should be positioned towards the moon for lunar exploration, the solar panel towards the sun for power generating, and the directional antenna towards the earth for transmitting the data back to the earth," Long said.

He said the sub-systems of the satellite, including the heat control system and power supply system, need to be adjusted as they will be influenced by the moon.

"We have worked out proper measures through numerous tests and experiments, to ensure the success of the three key steps," he said.