JINAN, May 17 (Xinhua) -- When the United States' space shuttle Endeavor blasted off on Monday, the Alpha Magnetic Spectrometer-2 (AMS-02), which features a thermal control system developed by Chinese scientists, attracted worldwide attention.

The thermal control system guarantees the stable temperature of the AMS-02 in space for the first time, said a spokesperson with Shandong University, a Chinese institution involved in developing the system.

AMS-02, which will be installed on the International Space Station (ISS), is a particle physics detector designed to study the universe and its origins by searching for antimatter and dark matter in space and by measuring cosmic rays.

The 2 billion U.S. dollar AMS-02 program, led by Nobel Prize Laureate Samuel Ting, attracted more than 600 researchers from 16 countries and regions, including China.

Shandong University joined the program in 2004 and was responsible for designing the thermal control system.

The team's task was to keep the detector's equipment working under a stable temperature, said Shandong University Chancellor Xu Xianming.

"The thermal environment in space is harsh. What we did was like putting clothes on the AMS-02, protecting it from a wide margin of temperature changes," said Cheng Lin, chief scientist of the thermal system.

As an external experiment module of the ISS, different areas of the detector are subject to direct solar illumination and exposure to deep space along with the revolution of the space station.

Therefore, the surface temperature of AMS-02 will vary from minus 40 degrees Celsius to 60 degrees Celsius.

Meanwhile, the detector's electronic equipment will consume electricity and release 2,500 joules of heat per hour.

Since the response of the components within the AMS-02 is temperature dependent, the temperature must be kept within different operational ranges and remain stable.

The research team at Shandong University collaborated with more than thirty scientists from institutions around the world, including Massachusetts Institute of Technology (MIT), Eidgenoossische Technische Hochschule Zurich (ETH Zurich) and the National Space Organization(NSPO), to test thermal simulations of AMS-02 in different seasons, operations and orbital positions.

Through a series of extensive modeling and testing, the performance of the thermal control system was validated in an overall test in the European Space Agency (ESA).

"The thermal control system is the foundation of the detector's normal operation. Any mistakes are unacceptable for our job," said Cheng, who is also a professor with the Institute of Thermal Science at Shandong University.

During the research phase, Cheng and his team developed more than ten advanced technologies with independent intellectual property rights.

Among these developments, the loop heat pipe is a world-leading instrument in the field of thermal control, and can be used in the thermal control systems of spacecrafts and cooling systems of electronic devices.

According to the program, once it is assembled, AMS-02 will send feedback to three data centers, including one in Shandong University, via a data relay satellite.

The recently-established Institute of Thermal Science will monitor AMS-02's orbital operation in real-time while analyzing and restructuring the received data.

AMS-02 was supposed to have been delivered to the ISS years ago, but its initial voyage was delayed after the Columbia disaster in 2003, which left seven astronauts dead.

The launch of Endeavor, scheduled to incorporate AMS-02, had been postponed several times prior to Monday's launch.

On April 29, the flight was postponed after engineers found a problem with one of its three heating units a few hours before the scheduled launch.

This is the Endeavor's final journey into space as the U.S. government has decided to end the 30-year-old shuttle program of the National Aeronautics and Space Administration (NASA) later this year.

Source:www.xinhuanet.com/english2010/