China Outer Space Science, Technology and Explorations: News & Updates

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China launches relay satellite to explore Moon's far side
Source: Xinhua| 2018-05-21 06:50:11|Editor: Yamei

A Long March-4C rocket carrying a relay satellite, named Queqiao (Magpie Bridge), is launched at 5:28 a.m. Beijing Time from southwest China's Xichang Satellite Launch Center, May 21, 2018. China launched a relay satellite early Monday to set up a communication link between Earth and the planned Chang'e-4 lunar probe that will explore the mysterious far side of Moon, which can not be seen from Earth. (Xinhua/Cai Yang)

XICHANG, May 21 (Xinhua) -- China launched a relay satellite early Monday to set up a communication link between Earth and the planned Chang'e-4 lunar probe that will explore the mysterious far side of Moon, which can not be seen from Earth.

The satellite, named Queqiao (Magpie Bridge), was carried by a Long March-4C rocket that blasted off at 5:28 a.m. from southwest China's Xichang Satellite Launch Center, according to the China National Space Administration (CNSA).

"The launch is a key step for China to realize its goal of being the first country to send a probe to soft-land on and rove the far side of the Moon," said Zhang Lihua, manager of the relay satellite project.

About 25 minutes after liftoff, the satellite separated from the rocket and entered an Earth-Moon transfer orbit with the perigee at 200 km and the apogee at about 400,000 km. The solar panels and the communication antennas were unfolded.

Queqiao is expected to enter a halo orbit around the second Lagrangian (L2) point of the Earth-Moon system, about 455,000 km from the Earth. It will be the world's first communication satellite operating in that orbit.

But the mission must overcome many challenges, including multiple adjustments to its orbit and braking near the Moon and taking advantage of the lunar gravity, Zhang said.

In a Chinese folktale, magpies form a bridge with their wings on the seventh night of the seventh month of the lunar calendar to enable Zhi Nu, the seventh daughter of the Goddess of Heaven, to cross and meet her beloved husband, separated from her by the Milky Way.

Chinese scientists and engineers hope the Queqiao satellite will form a communication bridge between controllers on Earth and the far side of the Moon where the Chang'e-4 lunar probe is expected to touch down later this year.

Monday's launch was the 275th mission of the Long March rocket series.

 

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Queqiao (Magpie Bridge)

 

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China to conduct record laser-ranging test
Source: Xinhua| 2018-05-21 14:16:38|Editor: Yurou


XICHANG, Sichuan Province, May 21 (Xinhua) -- Chinese scientists are to conduct a laser-ranging test between the relay satellite of the Chang'e-4 lunar probe and an observatory on the ground, which might help lay the foundation for space-based gravitational wave detection.

The relay satellite Queqiao, or Magpie Bridge, which was launched Monday, will fly to a halo orbit around the second Lagrangian point (L2) of the Earth-Moon system. It will be a communication link between controllers on Earth and the Chang'e-4 lunar probe, which is expected to soft-land on the far side of the Moon at the end of this year.

Chinese scientists will also conduct a laser-ranging test with the satellite at a maximum distance of 460,000 km, a record distance for an experiment of its kind, said Zhang Lihua, manager of the relay satellite project.

China has reportedly accomplished its first successful lunar laser-ranging, with a 1.2-meter telescope at southwest China's Yunnan Observatories on Jan. 22 this year, when scientists measured the distance between the Moon and the Earth, based on the signals of laser pulses reflected by the lunar retro-reflector planted by the U.S. Apollo mission more than 40 years ago.

Scientists calculated the time a laser pulse takes to travel from a ground station to the retro-reflector on the Moon and back again to get a measurement.

Just a few countries, including the United States, France and China, have successfully harnessed the lunar laser-ranging technology.

The Queqiao satellite, carrying a reflector developed by Sun Yat-sen University, is expected to extend laser-ranging to a new record distance.

As the satellite will fly at a constant high speed, it will be extremely hard for the laser beam from the ground to target the reflector on the satellite about 460,000 km away.

Luo Jun, an academician of the Chinese Academy of Sciences and president of Sun Yat-sen University, has proposed a space science program to detect gravitational waves. Laser-ranging is a necessary technology for that detection.

 

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Queqiao (Magpie Bridge)

View attachment 475554

China's Queqiao satellite carries 'large umbrella' into deep space

2018-05-21 15:15 Xinhua Editor: Gu Liping

An artist's illustration of China's Queqiao relay satellite, which will relay data between controllers on Earth and China's Chang'e 4 lander-rover pair on the moon's far side. (Photo/China National Space Administration)

The relay satellite, launched Monday for China's Chang'e-4 lunar probe, is carrying the largest communication antenna ever used in deep space exploration, according to Chinese experts.

The launch of the satellite Queqiao, or Magpie Bridge, is a key step for China to realize its goal of sending the Chang'e-4 lunar probe to soft-land on the far side of the Moon.

Queqiao, developed by China Spacesat Co., Ltd. under the China Academy of Space Technology (CAST), will be the world's first communication satellite operating in an orbit around the L2 point of the Earth-Moon system to establish a communication link between controllers on Earth and the probe.

Chinese experts designed several antennas for the relay satellite, including one shaped like an umbrella with a diameter of 5 meters, which opened in space after the satellite separated from the carrier rocket.

It must endure temperatures as cold as 230 degrees centigrade below zero. Chinese experts conducted countless experiments during the development of the antenna, said Chen Lan, deputy chief engineer of the Xi'an Branch of CAST.

The satellite is of great scientific and engineering importance in the exploration of the universe, said Zhang Lihua, manager of the relay satellite project.

A reliable long-distance data transmission link is a key technological goal for space experts around the world.

A relay satellite is a type of communication satellite that provides data transmission, observation and control services for other spacecraft.

China has already sent a series of relay satellites into geosynchronous orbit at an altitude of 36,000 km for manned spacecraft.

Queqiao is similar to those relay satellites, but its orbit is more than 10 times farther, which is the main technological difficulty.

http://www.ecns.cn/2018/05-21/303326.shtml

 

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NEWS 21 MAY 2018
China launches first part of ambitious mission to Moon’s far side
Two radio-astronomy experiments piggybacked on launch of Queqiao probe, which will act as a data-relay station for Chang'e-4 moon lander.

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The Queqiao spacecraft and two radio-astronomy experiments launched from the Xichang Space Centre in western China on 21 May.Credit: AFP/Getty

China has taken its first major step in a groundbreaking lunar mission. On 21 May, a probe launched from Xichang Space Centre to head beyond the Moon — where it will lie ready to act as a communications station for the Chang’e-4 lunar lander. The nation hopes that the Chang’e-4 lander will, later this year, become the first ever probe to touch down on the far side of the Moon.

The relay probe, named Queqiao and designed by the Chinese Academy of Sciences, also carries two pioneering radio-astronomy experiments. Both are proof-of-principle missions designed to test technologies for exploring a period in cosmic history known as the dark ages. These first few hundred million years, before galaxies and stars began to form, are all but impossible to study from the Earth. But the spectrum of radiation from this age — when matter was nearly uniformly distributed across space as a thin, cold haze — could reveal information about the relative distribution of ordinary matter versus dark matter in the Universe.

One experiment is the Netherlands-China Low-Frequency Explorer (NCLE), which will linger with Queqiao at a gravitational resting point called Earth–Moon L2 beyond the Moon that tracks the Moon’s orbit around Earth (see ‘Far-side satellite’). The Dutch-built experiment will try to exploit the relative quiet there to measure radio waves between about 1 megahertz and 80 megahertz, coming from the Solar System, the Galaxy and beyond. Much of this frequency band is blocked by Earth’s atmosphere but cosmologists expect it to contain information from the dark ages. (Around the upper end of this band also lie the ‘cosmic dawn’ signals from the first stars that lit up around 200 million years after the Big Bang, apparently detected for the first time by an experiment in Australia earlier this year. Other experiments are trying to replicate those results — but the NCLE is mainly looking for the lower-frequency signatures from the dark ages.)

Credit: National Astronomical Observatory of China/Chinese Academy of Sciences

For at least part of its orbit, Queqiao will be eclipsed by the Moon as seen from Earth, which could benefit the NCLE because its antennas will be further shielded from radio noise that constantly leaks from our planet. Still, observing time and the bandwidth for sending data back to Earth will be limited. And because Queqiao is primarily designed as a data-relay station (its name is from a folktale about magpies that form a bridge across the sky), it is not optimized for radio astronomy. That means it will be challenging, if not impossible, to detect the dark-ages signal with this demonstrator mission, says Heino Falcke, a radio astronomer at Radbound University in Nijmegen who is the experiment’s science leader. Nonetheless, the NCLE “is pioneering and an important first step toward investigating the dark ages and cosmic dawn”, says Jack Burns, an astrophysicist at the University of Colorado Boulder who is leading a proposal for a NASA mission with similar objectives.

Mission control will deploy the NCLE’s antennas only after the Chang’e-4 lander’s mission is completed, to avoid any risk of destabilizing the Queqiao probe, says Marc Klein Wolt, a Radboud astronomer who is NCLE’s manager. But the NCLE might go on collecting data for several years, he says.

Satellite break-off

The second experiment that launched with Queqiao consists of two smaller satellites called Longjiang-1 and Longjiang-2, which will detach from the mothership and orbit the Moon. Built by researchers at the Harbin Institute of Technology in China, the instruments will test technology for a radio astronomy technique called very long baseline interferometry (VLBI). This approach combines data from multiple radio antennas to get images of much higher resolution than would be possible with a single dish.

Falcke and others have long studied the possibility of doing VLBI with a large array of lunar orbiters — or on the lunar surface — to map variations across the sky in signals from the dark ages and cosmic dawn. Klein Wolt says that his team might experiment with combining data from NCLE with those from the two lunar orbiters and even from a radio antenna on the Chang’e-4 lander itself.

The Chang’e-4 mission is another step in China’s ambitious lunar-exploration programme, which aims to establish a Moon base in the next decade and to begin human exploration in the 2030s. The lunar lander will carry a rover and was originally designed as a back-up probe for Chang’e-3, which in 2013 became the first craft to soft-land (rather than crash-land) on the Moon since 1976. Chang’e-4 has now been repurposed, and the mission’s main scientific goal is to study the geology of the hidden side of the Moon, which is pockmarked with many more small craters than the familiar near side.

The lander carries experiments including a sealed ecosystem, built by Chongqing University, which will test whether potato and thale-cress (Arabidopsis) seeds sprout and photosynthesize while silkworm eggs hatch and worms produce carbon dioxide. Another experiment will measure the radiation that future astronauts who visit the lunar surface will be exposed to. The rover, which will separate from the lander to move around the surface, will carry instruments including a solar-wind detector built by a Swedish team.

doi: 10.1038/d41586-018-05231-9


China launches first part of ambitious mission to Moon’s far side | Nature

 

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QueQiao enroute to EML2. Weibo report first TCM(Trajectory Correction Maneuvers) performed.
Also amateur radio report receiving signal from both QueQiao and Longjiang.

https://twitter.com/x/status/998988775219974144

https://twitter.com/x/status/998994161033334784

 

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China's new space tech test a success

2018-05-24 09:21:30 Global Times Editor : Li Yan

China has successfully experimented with its space program's inflatable reentry and descent technology (IRDT), a technology that can allow China to land heavier spacecraft on celestial bodies with thin atmosphere, including the moon and Mars, specialists said.

The experiment, the first of its kind in China, China Aerospace Science and Technology Corporation (CASC) recently conducted on IRDT successfully validated working principles, working process and multiple key technologies, Science and Technology Daily reported on Wednesday.

The tested space vehicle was shaped like a flying saucer and covered in thick air bags - key components to the IRDT system. IRDT is a new integrated inflatable heat insulating deceleration system that can land spacecraft without heat shields and parachutes, the Beijing-based newspaper said.

Landing systems using technology like this can handle more weight than with deceleration systems of earlier generations. It will provide a more effective landing approach that would allow heavier spacecraft to land, Pang Zhihao, a Beijing-based rocket and aerospace expert, told the Global Times on Wednesday.

Current landing methods such as parachute landing and thrust reversal make it difficult for spacecraft to land on celestial bodies with thin atmosphere such as the moon and Mars. That is where IRDT excels at, Song Zhongping, a military expert and TV commentator, told the Global Times on Wednesday.

He added that IRDT provides buffer and protection to spacecraft while landing while inflating air bags which cover the spacecraft.

The U.S. conducted experiments in 2014 and 2015 on low density supersonic decelerators, a technology similar to China's IRDT, to land manned spacecraft and large robots on Mars. Although their attempts continue to face technical issues, the technology proved to be valuable, Pang said.

The IRDT will be used in deep space exploration and the quick return of space stations, scientific experiment satellites and space freight, Science and Technology Daily reported.

"It requires spacecraft to use different kinds of landing methods on different celestial bodies… China must consider new methods (like IRDT) to learn all technical approaches," Song noted, believing China will master the technology despite the challenges.

"China is looking to land on the moon and Mars. The new technology will be of great help."

China plans to launch its first spacecraft using this technology in 2019, the newspaper reported.

http://www.ecns.cn/news/sci-tech/2018-05-24/detail-ifyuqkxh5545069.shtml

 

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QueQiao enroute to EML2. Weibo report first TCM(Trajectory Correction Maneuvers) performed.

According to Chinese media report, because of high precision of orbital injection, TCM 2 and 3 were unnecessary and cancelled. The following maneuver, the lunar swing by was successfully performed as reported below.

Chinese relay satellite brakes near moon for entry into desired orbit
Source: Xinhua| 2018-05-26 01:28:23|Editor: yan


BEIJING, May 25 (Xinhua) -- A Chinese relay satellite Friday braked near the Moon, completing a vital step before entering a desired orbit, according to the China National Space Administration.

The satellite, Queqiao, braked 100 km above the surface of the Moon in line with instructions from a ground control center in Beijing, and then entered a transfer orbit from the moon to the second Lagrangian (L2) point of the Earth-Moon system.

"There was only a short window for the braking," said Zhang Lihua, project manager of the mission. "And Queqiao had only one chance due to limited fuel."

The relay satellite was launched Monday to set up a communication link between Earth and the planned Chang'e-4 lunar probe that will explore the Moon's mysterious far side.

The satellite is expected to adjust orbit several times before it reaches a halo orbit around the L2 point, about 455,000 km from the Earth.

It will be the world's first communication satellite operating in that orbit.

 

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The two Longjiang micro-satellites that were launched together with Queqiao was also reported to have enter lunar orbit.
DSLWP (Discovering the Sky at Longest Wavelengths Pathfinder) is alternate name for Longjiang.

https://twitter.com/x/status/999574248736702464

https://twitter.com/x/status/1000041106279550976

 

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Chinese astronauts complete desert survival training
Source: Xinhua| 2018-05-27 22:22:31|Editor: Xiang Bo

Taikonaut Liu Wang exits from a re-entry capsule during a wilderness survival training in the Badain Jaran Desert in northwest China's Gansu Province, May 17, 2018. Fifteen Chinese taikonauts have just completed desert survival training deep in the Badain Jaran Desert near Jiuquan Satellite Launch Center in northwest China. Organized by the Astronaut Center of China (ACC), the program was designed to prepare taikonauts with the capacity to survive in the wilderness in the event their re-entry capsule lands off target. (Xinhua/Chen Bin)

JIUQUAN, May 27 (Xinhua) -- Fifteen Chinese astronauts have just completed desert survival training deep in the Badain Jaran Desert near Jiuquan Satellite Launch Center in northwest China.

Organized by the Astronaut Center of China (ACC), the program was designed to prepare astronauts with the capacity to survive in the wilderness in the event their re-entry capsule lands off target.

Before venturing into space, astronauts have to survive in various hostile environments as a part of their technical training. Wilderness survival training is an important part of astronaut training in space agencies worldwide, leaving space mission candidates stranded at sea, in deserts, in jungles or on glaciers.

This is the latest survival training activity for Chinese astronauts after their sea survival training with two European astronauts in waters off the coast of Yantai in east China's Shandong Province in August 2017.

In the latest training program, each team, all wearing spacesuits, simulated an emergency landing scenario in which they needed to exit the capsule themselves, report their location and survive in the desert until rescue arrived 48 hours later.

In the desert, a land of extremes, the trainees had to handle the arid conditions, the daytime heat and cold at night.

The desert survival training tested the allocation of emergency supplies so their design can be improved in the future, said Huang Weifen, deputy chief designer at the ACC.

Chinese astronauts also completed emergency escape training on a launchpad in Jiuquan Satellite Launch Center, which has launched all manned spacecraft in the country.

The training programs were part of the comprehensive training of astronauts for China's space station.

China plans to start assembling its space station in space in 2020. It is scheduled to become fully operational around 2022.

 

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Spotlight: China welcomes all UN member states to jointly utilize its space station
Source: Xinhua| 2018-05-29 04:54:24|Editor: Chengcheng


VIENNA, May 28 (Xinhua) -- China announced Monday that all member states of the United Nations are welcome to cooperate with China to jointly utilize its future China Space Station (CSS).

"CSS belongs not only to China, but also to the world," said Shi Zhongjun, China's ambassador to UN and other international organizations in Vienna.

"All countries, regardless of their size and level of development, can participate in the cooperation on an equal footing," he said.

Interested public and private organizations, including institutes, academies, universities and private enterprises with scientific orientations, can identify their appropriate models of cooperation on board CSS, may it be the growth of a space plant, or even the accommodation of an astronaut, said the ambassador.

HOME OF COOPERATION FOR MUTUAL BENEFIT

CSS, expected to be launched by 2019, and complete and brought into operation by 2022, will be the world's first space station that is developed by a developing country and open for cooperation with all UN member states.

Consisting of one core module and two experiment modules, CSS will have the capacity to accommodate up to three astronauts at the same time and maximum six during rotation.

Operating in low-Earth orbit about 400 kilometers above the Earth's surface, CSS will be used in a wide range of research fields, including space medicine, life science, biotechnology, microgravity science, Earth science and space technology.

"Through the vehicle of CSS, we would like to build up a model of sincere mutual beneficial cooperation among countries in the peaceful exploration and use of outer space," said the Chinese ambassador.

As a developing country itself, China stands ready to help other developing countries in their development of space technology and space capacity building in particular, he said.

Guided by the idea of a shared future for mankind, CSS will be a home that is inclusive and open, a home of peace and goodwill, and a home of cooperation for mutual benefit, he added.

Priyani Wijesekera, ambassador of Sri lanka to the UN in Vienna, believes that CSS would benefit developing states like Sri lanka which lacks financial means and expertise to launch such a project.

"It's very interesting and we are looking forward to cooperating with China," she told Xinhua.

CHINA'S MOVE TO SHARE WELCOMED

Simonetta Di Pippo, director of the UN Office for Outer Space Affairs (UNOOSA) welcomed China's move to share its "state of the art space program" which is "one of the most holistic and technologically advanced in the world."

"With the global challenges we all face here on Earth, it is therefore important to foster collaboration and cooperation in the field of space activities," she said.

The director said technical advances in space have broader benefits to all humankind, as space is a driver and a tool for socio-economic sustainable development.

In 2016, the United Nations, represented by UNOOSA, confirmed its partnership with the China Manned Space Agency (CMSA) by signing a Memorandum of Understanding to allow "Access to Space" to all UN member states, developing countries in particular, to address all 17 Sustainable Development Goals by jointly utilizing CSS.

Following Monday's announcement, the UNOOSA has extended official letters to all Permanent Missions in Vienna and New York as well as offices of the United Nations Development Program, kicking off a three-month application period for public organizations, industries and private sector organizations with scientific orientation.

"By working together, the sky is no longer the limit," said Di Pippo.

"I believe that all the efforts that we are making together will be highly beneficial to our cooperation, to all Member States of the United Nations, and to the attainment of the Sustainable Development Goals," she said.

China's exploration into outer space has been at the core of global attention since the launch of the first Chinese satellite in 1970. The planned launch of CSS next year follows the launch of space laboratory, Tiangong-1, in 2011.

China has been consistent in its peaceful commitment to the outer space. Yang Liwei, China's first "taikonaut", exhibited the UN flag to the whole world on China's first space safari in 2003, followed by 10 more Chinese in his footsteps making trips into the outer space.

The core module of CSS is named Tianhe, or "Harmony of the Heavens" in the Chinese language, which conveys China's hope to promote mutual trust and peace through cooperation aboard CSS.

Maria Assunta Accili Sabbatini, Italy's ambassador to the UN in Vienna, said the project offers a great opportunity for Italy as the two countries' space agencies have maintained close ties.

"We believe this opens a lot of room for cooperation," she said.

***

From UN Office for Outer Space Affairs (UNOOSA) -> UN and China invite applications to conduct experiments on-board China's Space Station

 

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Chang'e-4: Lunar microsatellite may be lost, Queqiao continues toward Lagrange point beyond Moon
by Andrew Jones May 28, 2018 12:38 MOON CHINA'S SPACE PROGRAM CHANG'E-4

A render of the Longjiang-1 and -2 (DSLWP-A/B) microsatellites in formation. Harbin Institute of Technology
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Contact has been lost with one of two microsatellites launched along with the Queqiao Chang'e-4 lunar relay satellite following a standard trajectory correction manoeuvre on the way to the Moon.

DSLWP-A and B, also known as Longjiang-1 and -2, piggybacked on the launch of Queqiao, a relay satellite for a planned landing on the lunar far side, on a Long March 4C rocket from Xichang on May 20.

Queqiao passed the Moon at an altitude of 100 km on Friday, successfully performing a braking burn to send it towards its intended destination, the second Earth-Moon Lagrange point, from which it will facilitate communications between the Earth and a lander and rover to be sent to the far side of the Moon.

The Discovering the Sky at Longest Wavelengths Pathfinder (DSLWP) satellites were intended to execute burns to place them in an elliptical (200 x 9,000 km) orbit around the Moon, where they would carry out astronomy and amateur radio tests.

While DSLWP-B/Longjiang-2 successfully entered lunar orbit, there has been apparently no communication between the ground and Longjiang-1 following a trajectory correction manoeuvre after trans-lunar injection.


Attempts to regain contact with the 45 kg, 50x50x40-cm satellite have also been made through a network of amateur radio and satellite tracking enthusiasts, both by those following the satellites from launch and following a request from those involved in the mission at Harbin Institute of Technology (HIT).

Amateurs have picked up telemetry from Longjiang-2/DSLWP-B since early in the mission, but the silence from Longjiang-1/DSLWP-A persists.

Official updates are awaited from the China National Space Administration (CNSA) or HIT. A loss of the microsatellite would not impact China's plans for the lunar far side landing.


Interferometry plans
The DSLWP project is led by HIT, with payload and science teams from the National Space Science Centre (NSSC) and the National Astronomical Observatories (NAOC), both under the Chinese Academy of Sciences (CAS).

The DSLWP satellites (later named Longjiang on April 24) were designed to test low-frequency radio astronomy in lunar orbit as well as space-based interferometry while in formation, between 1 and 10 km apart. The loss, if confirmed, would put an end to those plans.

The interferometry experiments would have seen the observations made simultaneously by the DSLWP/Longjiang microsatellites to be combined. The test would be verification of technology for a constellation of small, low-frequency radio astronomy satellites that would emulate a telescope with a size equal to the maximum separation between the satellites.

Testing on the Chang'e-4 DSLWP-A1 and DSLWP-A2 microsatellites in early 2018. CCTV/Youtube/Framegrab​

The Chang'e-4 mission could however see some interferometry tests carried out, with Queqiao carrying the Netherlands-China Low-frequency Explorer (NCLE) astronomy instrument, and a Low Frequency Spectrometer (LFS) on the Chang'e-4 lander, which is expected to launch in November or December, following testing of Queqiao.

Longjiang-2/DSLWP-B, as well as carrying low frequency (1-30 MHz) antenna and amateur radio payloads, also has a camera aboard, developed by Saudi Arabia.

Queqiao heads to Earth-Moon L2
Meanwhile, the Queqiao Chang'e-4 relay satellite passed the Moon and successfully performed a propulsive manoeuvre to slow itself and send it towards its a position beyond the Moon.

The Beijing Aerospace Control Centre (BACC) issued the command at 21:32 Beijing time (13:32 UTC) on May 25, and by 21:46 confirmed through telemetry that Queqiao had performed the burn and entered a transfer orbit towards the second Earth-Moon Lagrange point (EML2).

Failure to perform the braking manoeuvre would have seen the spacecraft head back towards the Earth.

Queqiao is expected to arrive at EML2 on May 29. It will then put itself into a halo orbit around the gravitationally stable point, allowing it constant line of sight with both tracking stations on Earth and the far side of the Moon, which is never visible to the Earth.

Image demonstrating a halo orbit around the second Earth-Moon Lagrange point, from which the Chang'e-4 communications relay satellite will operate. NAOC/CAS

It will later facilitate communications between and a lander and rover, set to land in Von Karman crater, using a 4.2 metre parabolic antenna.

It also carries a pioneering low-frequency astronomy instrument that will attempt to detect a signal from the cosmic dark ages, the NCLE.

For latest news and developments on the mission, see our feature on China's Chang'e-4 mission to the far side of the Moon

An animated demonstration of the role of the Queqiao Chang'e-4 lunar relay satellite. CAS​

Chang'e-4: Lunar microsatellite may be lost, Queqiao continues toward Lagrange point beyond Moon | GBTIMES.com

 

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Chinese rocket scientists design smart firefighter suit
Source: Xinhua| 2018-05-30 19:03:49|Editor: Yurou


BEIJING, May 30 (Xinhua) -- Chinese rocket scientists and engineers are turning their expertise to developing an intelligent firefighter suit that has cooling capability and can help track the location of the firefighters.

The intelligent suit was developed by the China Academy of Launch Vehicle Technology (CALT).

According to Wang Sifeng from CALT, the suit features rapid cooling capability. When the firefighter wears it in the fire, its temperature can drop to between 20 and 25 degrees Celsius within a minute.

High temperatures are one of the challenges for firefighters, but most firefighter suits in China do not help with cooling.

"The suit is equipped with a cooling system and replaceable cold storage materials. When the materials do not have enough cooling capacity, the suit will automatically issue a warning," Wang said.

CALT scientists also applied rocket navigation technology in designing the suit, which can send accurate firefighter positioning information to a background system in real time, thus enhancing the safety of firefighters.

The smart suit is going through several tests before use.

 

[JSCh]

Chang'e-4: Lunar microsatellite may be lost, Queqiao continues toward Lagrange point beyond Moon
by Andrew Jones May 28, 2018 12:38 MOON CHINA'S SPACE PROGRAM CHANG'E-4

A render of the Longjiang-1 and -2 (DSLWP-A/B) microsatellites in formation. Harbin Institute of Technology
​

Contact has been lost with one of two microsatellites launched along with the Queqiao Chang'e-4 lunar relay satellite following a standard trajectory correction manoeuvre on the way to the Moon.

DSLWP-A and B, also known as Longjiang-1 and -2, piggybacked on the launch of Queqiao, a relay satellite for a planned landing on the lunar far side, on a Long March 4C rocket from Xichang on May 20.

Queqiao passed the Moon at an altitude of 100 km on Friday, successfully performing a braking burn to send it towards its intended destination, the second Earth-Moon Lagrange point, from which it will facilitate communications between the Earth and a lander and rover to be sent to the far side of the Moon.

The Discovering the Sky at Longest Wavelengths Pathfinder (DSLWP) satellites were intended to execute burns to place them in an elliptical (200 x 9,000 km) orbit around the Moon, where they would carry out astronomy and amateur radio tests.

While DSLWP-B/Longjiang-2 successfully entered lunar orbit, there has been apparently no communication between the ground and Longjiang-1 following a trajectory correction manoeuvre after trans-lunar injection.


Attempts to regain contact with the 45 kg, 50x50x40-cm satellite have also been made through a network of amateur radio and satellite tracking enthusiasts, both by those following the satellites from launch and following a request from those involved in the mission at Harbin Institute of Technology (HIT).

Amateurs have picked up telemetry from Longjiang-2/DSLWP-B since early in the mission, but the silence from Longjiang-1/DSLWP-A persists.

Official updates are awaited from the China National Space Administration (CNSA) or HIT. A loss of the microsatellite would not impact China's plans for the lunar far side landing.


Interferometry plans
The DSLWP project is led by HIT, with payload and science teams from the National Space Science Centre (NSSC) and the National Astronomical Observatories (NAOC), both under the Chinese Academy of Sciences (CAS).

The DSLWP satellites (later named Longjiang on April 24) were designed to test low-frequency radio astronomy in lunar orbit as well as space-based interferometry while in formation, between 1 and 10 km apart. The loss, if confirmed, would put an end to those plans.

The interferometry experiments would have seen the observations made simultaneously by the DSLWP/Longjiang microsatellites to be combined. The test would be verification of technology for a constellation of small, low-frequency radio astronomy satellites that would emulate a telescope with a size equal to the maximum separation between the satellites.

Testing on the Chang'e-4 DSLWP-A1 and DSLWP-A2 microsatellites in early 2018. CCTV/Youtube/Framegrab​

The Chang'e-4 mission could however see some interferometry tests carried out, with Queqiao carrying the Netherlands-China Low-frequency Explorer (NCLE) astronomy instrument, and a Low Frequency Spectrometer (LFS) on the Chang'e-4 lander, which is expected to launch in November or December, following testing of Queqiao.

Longjiang-2/DSLWP-B, as well as carrying low frequency (1-30 MHz) antenna and amateur radio payloads, also has a camera aboard, developed by Saudi Arabia.

Queqiao heads to Earth-Moon L2
Meanwhile, the Queqiao Chang'e-4 relay satellite passed the Moon and successfully performed a propulsive manoeuvre to slow itself and send it towards its a position beyond the Moon.

The Beijing Aerospace Control Centre (BACC) issued the command at 21:32 Beijing time (13:32 UTC) on May 25, and by 21:46 confirmed through telemetry that Queqiao had performed the burn and entered a transfer orbit towards the second Earth-Moon Lagrange point (EML2).

Failure to perform the braking manoeuvre would have seen the spacecraft head back towards the Earth.

Queqiao is expected to arrive at EML2 on May 29. It will then put itself into a halo orbit around the gravitationally stable point, allowing it constant line of sight with both tracking stations on Earth and the far side of the Moon, which is never visible to the Earth.

Image demonstrating a halo orbit around the second Earth-Moon Lagrange point, from which the Chang'e-4 communications relay satellite will operate. NAOC/CAS

It will later facilitate communications between and a lander and rover, set to land in Von Karman crater, using a 4.2 metre parabolic antenna.

It also carries a pioneering low-frequency astronomy instrument that will attempt to detect a signal from the cosmic dark ages, the NCLE.

For latest news and developments on the mission, see our feature on China's Chang'e-4 mission to the far side of the Moon

An animated demonstration of the role of the Queqiao Chang'e-4 lunar relay satellite. CAS​

Chang'e-4: Lunar microsatellite may be lost, Queqiao continues toward Lagrange point beyond Moon | GBTIMES.com

DSLWP-A/LongJiang-1 might not be lost as reported.

https://twitter.com/x/status/1002089586678317056

Also, 9ifly.cn forum member below report HIT say signal from both DSLWP/LongJiang were received.

傲立风雨满庭芳 发表于 2018-5-31 15:05 来自航空航天港手机版！ | 只看该作者
哈工大的学长表示，可以松口气了。
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