On December 12, President Hu Jintao declared that China had
joined other countries having the capability for deep space
exploration.
The capability for deep space exploration includes the potential
to enter space, satellite development and application, space
foundation and protection, manned spaceflight as well as space
exploration, all of which can be attributed to many technical
breakthroughs inside China within the past three years.
China's first lunar exploration program has been very
successful, demonstrating outstanding wisdom on the part of the
Chinese scientists.
A math genius designed the orbits of Chang'e
I
Chang'e-I traveled over 380,000 kilometers before approaching
the moon, consuming a total of 14 days.
Yang Weilian, a 66-year-old orbit designer born in Jiande,
Zhejiang Province, plotted the route of Chang'e-I.
Yang Weilian was admitted to Peking University with a full score
in math, his chosen major. The China Academy of Space Technology
sent him abroad to study. His American peers praised him because he
ingeniously settled many mathematical problems.
Orbit design is a new subject, involving three-dimensional
problems and factoring in the gravitational forces of the earth and
moon. The designers had to try and make forecasts using many
complex calculations.
The designing group led by Yang, first assumed that the lunar
probe would take flight in two stages. Then they finally worked out
a suitable transfer orbit for Chang'e I after continuous
corrections.
The fuel saved by accurate orbital maneuvers will help prolong
the working time of Chang'e-I by about one year, with two
corrections being cancelled, said an expert with the Commission of
Science Technology and Industry for National Defense of the
People's Republic of China (COSTIND).
Female designer tackled technical difficulties of
carrier rocket
Chang'e-I, China's first lunar probe, blasted off on a Long
March 3A carrier rocket at 6:05 PM at the Xichang Satellite Launch
Center of southwestern Sichuan Province on October 24, 2007, with a
real error of only 0.4 second.
The Long March 3A has sent 15 satellites into space. It was
originally designed to launch the "Dongfanghong 3"
telecommunications satellites in the 1980's. The carrier has been
dubbed the "gold medal rocket" because it has a history of zero
defects.
Ms. Luo Qiaojun is a vice chief designer for the Long March 3A.
She began to work at Beijing Aerospace Propulsion Institution in
1989 and has been engaged in research on hydrogen-oxygen
engines.
Luo has initiated a technical innovation to resolve the problem
of helium leak inside whole engines. A national patent has been
applied for the new technology, which is one of the five key
technical improvements in the lunar probe program.
The home-make CCD camera can do the job of
three
The China National Space Administration (CNSA) released the
first picture of the moon captured by Chang'e-I on Nov. 26,
captured by the CCD camera aboard the lunar probe. The Xi'an
Institute of Optics and Precision Mechanics, inside the Chinese
Academy of Sciences (CAS), designed the camera. Zhao Baochang, a
specialist in optics, was the chief designer of the CCD camera.
Zhao Baochang has conducted research into technologies focused
on photoelectric tests, space optics observation and interference
spectrum imaging for 45 years. He is also a pioneer in high-speed
photography technology.
Three cameras are needed to obtain three-dimensional images of
the moon. Considering the limited launch capacity of rockets made
in China, researchers have had to be very creative. They applied
wide-angle lens and skillfully designed an optical-mechanical
system. The CCD camera can do the job of three, with simplified
structures and lighter weight, plus it cost significantly less,
said Assistant Chief Engineer Sun Huixian.
"Many scientists simply burst into tears when they saw the high
definition pictures taken by the home-made camera, the pictures are
much better than expected," said Sun Laiyan, vice director of
COSTIND and director of the CNSA.
A giant antenna to receive data sent back by
Chang'e-I
The survey and command system has formed a bottleneck in China's
moon exploration program.
A giant antenna, 50 meters in diameter, was designed in October
2002. After a check up it was accepted and began trial operations
in October 2006, specifically to receive data sent back by Chang'e
I.
Moreover, based on self-innovation, Chinese workers suggested
that a measurement network should be built comparable to the size
of China's territory, and designed like a huge telescope to improve
measurement accuracy.
"Scientists will do data mining based on the large amount of
statistics collected by the lunar probe. The statistics will be
released throughout China's scientific community. Some statistics
may be used in international exchanges according to common
practice, with part of them designated for technical
interchanges,"said Sun Jiadong, chief designer of the moon
exploration program.
(China.org.cn by Yang Xi, December 25, 2007)