Chinese scientists start studying samples from Shenzhou-7
7/10/2008 15:56
Chinese scientists yesterday unsealed a box of solid lubricant samples
that were aboard the Shenzhou-7 spacecraft. They will study the material for the
next six months.
"Two types of solid lubricant samples, after being exposed
to outer space during the Shenzhou-7 mission, had shown obvious changes," said
Liu Weimin, head of the Lanzhou Institute of Chemical Physics of the Chinese
Academy of Sciences in northwest Gansu Province.
"The appearance of the two
types of samples has either turned dark or become rougher," he said.
Solid
lubricants are widely used in spacecraft to reduce friction because they
withstand high temperatures.
Scientists hoped to improve the stability and
lifetime of the materials by studying the test samples taken to outer
space.
Liu said scientists would compare the samples with those exposed to a
simulated space environment in the laboratory.
"We need to know how the
lubricants react to being in a vacuum, atomic oxygen and low temperatures in
outer space," he said.
If scientists discover the difference between the two
exposed lubricants, they might be able to tell how other materials change in
outer space, Liu said.
The solid lubricant samples, loaded outside the
Shenzhou-7 capsule and retrieved by astronaut Zhai Zhigang during his spacewalk,
weighed about 2.2 kg. They were exposed to outer space for 44 hours.
The
Shenzhou-7 space module, carrying three taikonauts, landed safely by parachute
on Sept. 28 in China's northern grasslands after a 68-hour flight. The mission
included the first ever spacewalk by a Chinese astronaut.
Xinhua
|
