Hainan, April 29
(Xinhua) -- China on Thursday sent into space the core module of its space
station, kicking off a series of key launch missions that aim to complete the
construction of the station by the end of next year.
The Long March-5B
Y2 rocket, carrying the Tianhe module, blasted off from the Wenchang Spacecraft
Launch Site on the coast of the southern island province of Hainan at 11:23
a.m. (Beijing Time).
About 494 seconds
later, Tianhe separated from the rocket and entered the planned orbit. At 12:36
p.m., its solar panels unfolded and started to work properly.
The successful
launch of the core module marks that China's space station construction has
entered the full implementation stage, which lays a solid foundation for the
follow-up tasks, said Chinese President Xi Jinping in a congratulatory message.
On behalf of the
Communist Party of China (CPC) Central Committee, the State Council and the
Central Military Commission (CMC), Xi, also general secretary of the CPC
Central Committee and chairman of the CMC, extended warm congratulations and
sincere greetings to all members who have participated in the mission in the
message.
Tianhe will act as
the management and control hub of the space station Tiangong, meaning Heavenly
Palace, with a node that could dock with up to three spacecraft at a time for
short stays, or two for long, said Bai Linhou, deputy chief designer of the
space station at the China Academy of Space Technology (CAST), under the China
Aerospace Science and Technology Corporation.
Tianhe has a total
length of 16.6 meters, a maximum diameter of 4.2 meters and a takeoff mass of
22.5 tonnes, and is the largest spacecraft developed by China.
The space station
will be a T shape with the core module at the center and a lab capsule on each
side. Each module will be over 20 tonnes. When the station docks with both
manned and cargo spacecraft, its weight could reach nearly 100 tonnes.
The station will
operate in the low-Earth orbit at an altitude from 340 km to 450 km. It has a
designed lifespan of 10 years, but experts believe it could last more than 15
years with appropriate maintenance and repairs.
"We will learn
how to assemble, operate and maintain large spacecraft in orbit, and we aim to
build Tiangong into a state-level space lab supporting the long stay of
astronauts and large-scale scientific, technological and application
experiments," said Bai.
"The station
is also expected to contribute to the peaceful development and utilization of
space resources through international cooperation, as well as to enrich
technologies and experience for China's future explorations into deeper
space," Bai said.
LIFE SUPPORT SYSTEM
As the foundation
of the station, Tianhe will help China's aerospace engineers carry out the
verification of key technologies, including flexible solar wings, in-orbit
assembly and maintenance, and above all a new life support system.
China will also
send the Tianzhou-2 cargo spacecraft and Shenzhou-12 manned craft this year to
dock with the core module. Three astronauts will be aboard Shenzhou-12 and stay
in orbit for three months, said Hao Chun, director of the China Manned Space
Agency (CMSA).
"We will
transport support materials, necessary spare parts and equipment first, and
then our crew," said Hao.
Tianzhou-3 cargo
craft and Shenzhou-13 manned spaceship will also be launched later this year to
dock with Tianhe, and another three astronauts will then begin their six-month
stay in orbit.
The longest stay in
space so far by Chinese astronauts is 33 days. "In previous missions, we
sent water and oxygen to space along with astronauts. But for a stay of three
to six months, water and oxygen would stuff the cargo craft full with no room
for other necessary goods and materials. So we installed the core module with a
new life support system to recycle urine, exhaled breath condensate (EBC) and
carbon dioxide," said Bai.
With the system,
urine can be processed into distilled water, some of which can be used for
toilet flushing and the rest, together with the collected EBC water, can be
further purified for electrolytic oxygen generation and experiments, said Cui
Guangzhi, a designer of the urine treatment system, a sub-system of the life
support system, with the Second Institute of the China Aerospace Science and
Industry Corporation Limited (CASIC).
"The recycling
of water can reduce the load burden of cargo craft and greatly cut the
operating cost of the space station," Cui said.
Bai Linhou stressed
the life support system was challenging. "It has never been used in
China's previous space missions. The different gravity environment in space
makes it hard to perfect the technology on the ground."
"The life
support technology is a must for astronauts to stay on the moon or explore
deeper space. We will develop the technology step by step, first recycling
water and oxygen in Tiangong, and then planting vegetables and crops in space
to gradually realize food self-sufficiency," Bai added.
TECHNOLOGY
INNOVATION
After the five
launch missions this year, China plans six missions, including the launch of
the Wentian and Mengtian lab modules, two cargo spacecraft and two manned
spaceships, in 2022 to complete the construction of the space station.
"We have to
make sure every launch is reliable and operation of spacecraft in orbit is safe
and sound. Every mission is a test for our organization, management, technology
and support ability," said Zhou Jianping, chief designer of China's manned
space program.
The station will
offer astronauts more than 100 cubic meters of room for living and working,
more than six times that of Tiangong-2 space lab. The core module Tianhe will
provide astronauts six zones respectively for work, sleep, sanitation, dining,
healthcare and exercise.
If Tiangong-1 and
Tiangong-2 are like one-bedroom apartments, the space station is equivalent to
an apartment with three bedrooms, a living room, a dining room and a storage
room.
Researchers and
engineers have also made work and life in space more comfortable and convenient
through advanced information and AI technologies.
Astronauts can
control cabin lighting and kitchen equipment through handset APP and phone each
other or communicate with the ground wirelessly. The large bandwidth can also
support transmission of huge amounts of experiment data to the ground.
The faster
space-ground network speed will also allow the engineers to upload modified software
programs to the space station.
The mechanical arms
installed on the space station will help astronauts in their assembly,
operation and maintenance work of the station.
The station also
has more advanced technologies thanks to the collected wisdom and strength from
universities, research institutes and industrial departments across the
country.
It will be more
energy efficient, with the photoelectric conversion efficiency of its
photovoltaic system exceeding 30 percent, and by using electric propulsion
rather than conventional chemical propulsion, Zhou said.
THREE-STEP STRATEGY
In 1992, China
started the manned space program with a three-step strategy. "Progress
steadily with systematic and long-term planning - this is a good example of how
China does things," said Zhou.
The first step was
to send astronauts into space and return safely. The launches of Shenzhou-5 in
2003 and Shenzhou-6 in 2005 fulfilled the mission.
The second step was
to test key technologies needed for a permanent space station, including
extra-vehicular activity, orbital docking, and in-orbit propellant refueling.
This phase included
the launch of Tiangong-1, a transitional platform to test the docking
technology, and the Tiangong-2 space lab.
China has launched
11 manned spacecraft, one cargo spacecraft, Tiangong-1 and Tiangong-2, sending
11 astronauts into space and completing the first two steps of the manned space
program.
The third step is
to assemble and operate a permanently crewed space station, which will mark a
new high in China's space technology.
Bai Linhou said the
station could support at most six astronauts at the same time. Regular launches
of crewed and cargo spaceships will secure a long-term manned presence to carry
out in-orbit research and services.
Flight engineers
and payload experts are among the astronaut reserve for the first time to meet
the space station's maintenance and advanced research needs.
Such a large
facility will provide many opportunities for scientific research and
technological experiments, said Zhou. "It is bound to enrich our
understanding of the universe and promote the development in science,
technology, and applications."
Seed breeding,
pharmaceutical research, and development of critical materials in the space
station are expected to produce economic benefits. The life support technology
and energy technology are also likely to benefit economic and social
development.
Hao Chun said the
space station would become an excellent platform for popular science education,
such as online courses from space and demonstration of space science projects
designed by school students.
In June 2013,
female astronaut Wang Yaping delivered the country's first televised science
lesson from space to an audience of over 60 million schoolchildren and teachers
across China. The class lasted for 40 minutes on basic physics principles and
ignited the space dreams of millions of Chinese students.
BENEFIT ALL
HUMANKIND
Since China started
to develop its manned space program, it has been carrying out international
cooperation with an open attitude by adhering to the principle of peaceful use
of space and win-win sharing.
For the space
station project, China has extensive exchanges and cooperation with the United
Nations Office for Outer Space Affairs (UNOOSA), the European Space Agency, and
national space agencies from countries like Germany, Italy, France and
Pakistan.
The cooperation has
covered multiple fields, including technologies, science research and
application, and astronaut selection and training, producing many achievements.
In March 2016, the
CMSA and the UNOOSA signed a memorandum of understanding to invite UN member
states to conduct scientific experiments aboard the China space station. In May
2018, 27 countries brought forward 42 cooperation proposals after the two
agencies sent out the invitation.
In June 2019, China
released the first batch of nine jointly-selected international cooperation
projects, involving 17 countries in aerospace medicine, life sciences and
biotechnology, microgravity physics and combustion science, astronomy, and
other emerging technologies.
According to Hao,
the research projects are being carried out as planned, and China will continue
to solicit cooperation projects globally with the UNOOSA.
The payloads at the
space station will be updated constantly, explained Bai. Cargo spaceships will
send new payloads and remove the old, ensuring continuous opportunities for new
international projects.
"We would like
to see foreign astronauts participate in China's space flight missions, working
and living in China's space station in the future," Hao noted.
He said many
foreign space agencies had brought up cooperative intentions, and China will
start the selection of foreign astronauts and carry out joint flights according
to the mission progress.
"Through
cooperation, we want to build China's space station into a scientific research
platform shared by the world and benefiting all humankind," Hao said.