The chance for amateur astronomy buffs to observe China's first moon orbiter, likely to be launched on Wednesday, is very slim, Chinese space experts said on Tuesday.

The circumlunar satellite, named Chang'e I, is very tiny in open space as it is only 18.1 meters long even when its solar energy board is fully extended, said Sun Zezhou, deputy chief designer of the satellite.

The satellite is very much likely to be invisible since it is neither illuminated nor covered with a special surface to reflect light, he said.

"Meanwhile, the satellite will travel at a speed of seven to eight kilometers per second. An amateur telescope will not catch it, let alone follow it," said Chen Xianfeng, an expert with Beijing Space Command and Control Center.

"It is very hard to observe it even with a professional telescope. The control center will follow Chang'e I by signals it sends and when it enters the moon's orbit, some 380,000 km away from the earth, the satellite will be invisible even to the world's largest optic telescope," Chen said.

According to a spokesman for the China National Space Administration (CNSA) Monday, Chang'e I will be launched between October 24 and 26 and the first choice is around 6 p.m. on Oct.24.

The satellite will relay the first picture of the moon in late November and will then continue scientific explorations of the moon for a year.