BEIJING -- China's first lunar probing satellite, Chang'e-1, will be put to test Thursday morning when the Earth eclipses the Sun and blocks the supply of solar energy.

From about 10 a.m., the satellite will be hidden from the solar rays and lost the contact from the Earth for two and a half hours, said Ye Peijian, chief commander and designer in charge of the satellite system.

Scientists have redirected the orbit of the satellite and shortened the time it is out of direct sunlight by almost one hour and a half, Ye said.

Ye said the European Space Agency would also help to monitor the satellite and the final results would not be clear until this evening.

The satellite would also perform a second orbital adjustment during another eclipse in August, he said.

The 2,350-kilogram satellite carrying eight surveying facilities aims to make a three-dimensional survey of the moon's surface. It will also analyze the abundance and distribution of elements on the lunar surface,investigate the characteristics of the powdery soil layer on the surface, and explore the environment between the Earth and the moon.

This is the first step in China's three-stage moon mission, which will lead to a landing and launch of a rover vehicle around 2012. In the third phase, another rover will land and return to the Earth with lunar soil and stone samples for scientific research around 2017.