Chinese Unmanned Lunar Orbiter Returns Home Safely, Paves Path for Ambitious Lunar Sample Return

A Chinese robotic probe has just successfully completed the first round trip to the Moon and back home in four decades that paves the path for China’s next great space leap forward – an ambitious mission to return samples from the lunar surface later this decade.

On Saturday, Nov. 1, the unmanned Chang’e-5 T1 test capsule nicknamed “Xiaofei” concluded an eight-day test flight around the Moon by safely landing in Siziwang Banner of China’s Inner Mongolia Autonomous Region, according to a report by the official Xinhua News agency.

China thus become only the third nation to demonstrate lunar return technology following the former Soviet Union and the United States. The Soviet Union conducted the last lunar return mission in the 1970s.

Search teams with helicopters recovered the “Xiaofei” orbiter intact at the planned landing zone about 500 kilometers away from Beijing.

The Chang’e-5 T1 test mission is an unequivocally clear demonstration of China’s mounting technological prowess.

Researchers retrieve the return capsule of China's unmanned lunar orbiter in the central region of north China's Inner Mongolia Autonomous Region, Nov. 1, 2014. Return capsule of China's test lunar orbiter landed successfully early Saturday morning in north China's Inner Mongolia Autonomous Region, according to the Beijing Aerospace Control Center. Credit: Xinhua/Ren Junchuan
Researchers retrieve the return capsule of China’s unmanned lunar orbiter in the central region of north China’s Inner Mongolia Autonomous Region, Nov. 1, 2014. Return capsule of China’s test lunar orbiter landed successfully early Saturday morning in north China’s Inner Mongolia Autonomous Region, according to the Beijing Aerospace Control Center. Credit: Xinhua/Ren Junchuan

Chang’e-5 T1 served as a technology testbed and precursor flight for China’s planned Chang’e-5 probe, a future mission aimed at conducting China’s first lunar sample return mission in 2017.

“Chang’e-5 is expected to collect a 2-kg sample from two meters under the Moon’s surface and bring it home,” according to Wu Weiren, chief designer of China’s lunar exploration program.

The ability to gather and analyze pristine new soil and rocks samples from the Moon’s surface would be a boon for scientists worldwide seeking to unlock the mysteries of the solar system’s origin and evolution.

“Xiaofei” was launched on Oct. 23 EDT/Oct. 24 BJT atop an advanced Long March-3C rocket at 2 AM Beijing local time (BJT), 1800 GMT, from the Xichang Satellite Launch Center in China’s southwestern Sichuan Province.

Liftoff of the unmanned Chang'e-5 T1 lunar spacecraft atop a Long March-3C rocket from the Xichang Satellite Launch Center in China on Oct. 24, 2014, BJT (Oct. 23 EDT).  Credit: Xinhua/Jiang Hongjing
Liftoff of the unmanned Chang’e-5 T1 lunar spacecraft atop a Long March-3C rocket from the Xichang Satellite Launch Center in China on Oct. 24, 2014, BJT (Oct. 23 EDT). Credit: Xinhua/Jiang Hongjing

It was boosted on an 840,000 kilometer, eight-day mission trajectory that swung halfway around the far side of the Moon and back. It did not enter lunar orbit.

During its path finding journey, “Xiaofei” captured incredible imagery of the Moon and Earth, eerie globes hanging together in the ocean of space.

A unique view of the Moon and distant Earth from China's Chang’e-5 T1 lunar test flight. Image via CCTV News and UnmannedSpaceflight.com.
A unique view of the Moon and distant Earth from China’s Chang’e-5 T1 lunar test flight. Image via CCTV News and UnmannedSpaceflight.com.

The probe was developed by the China Aerospace Science and Technology Corporation. The service module is based on China’s earlier Chang’e-2 spacecraft.

On its return, the probe hit the Earth’s atmosphere at around 6:13 a.m. Saturday morning at about 11.2 kilometers per second for reentry and a parachute assisted soft landing in north China’s Inner Mongolia Autonomous Region.

The goal was to test and validate guidance, navigation and control, heat shield, and trajectory design technologies required for the sample return capsule’s safe re-entry following a lunar touchdown mission and collection of soil and rock samples from the lunar surface – planned for the Chang’e-5 mission.

“To help it slow down, the craft is designed to ‘bounce’ off the edge of the atmosphere, before re-entering again. The process has been compared to a stone skipping across water, and can shorten the ‘braking distance’ for the orbiter,” according to Zhou Jianliang, chief engineer with the Beijing Aerospace Command and Control Center.

“Really, this is like braking a car,” said Zhou, “The faster you drive, the longer the distance you need to bring the car to a complete stop.”

China hopes to launch the Chang’e-5 mission in 2017 as the third step in the nation’s ambitious lunar exploration program.

The first step involved a pair of highly successful lunar orbiters named Chang’e-1 and Chang’e-2 which launched in 2007 and 2010.

The second step involved the hugely successful Chang’e-3 mothership lander and piggybacked Yutu moon rover which safely touched down on the Moon at Mare Imbrium (Sea of Rains) on Dec. 14, 2013 – marking China’s first successful spacecraft landing on an extraterrestrial body in history, and chronicled extensively in my reporting here.

This time-lapse color panorama from China’s Chang’e-3 lander shows the Yutu rover at two different positions during its trek over the Moon’s surface at its landing site from Dec. 15-18, 2013. This view was taken from the 360-degree panorama. Credit: CNSA/Chinanews/Ken Kremer/Marco Di Lorenzo.   See our complete Yutu timelapse pano at NASA APOD Feb. 3, 2014:  http://apod.nasa.gov/apod/ap140203.htm
This time-lapse color panorama from China’s Chang’e-3 lander shows the Yutu rover at two different positions during its trek over the Moon’s surface at its landing site from Dec. 15-18, 2013. This view was taken from the 360-degree panorama. Credit: CNSA/Chinanews/Ken Kremer/Marco Di Lorenzo. See our complete Yutu timelapse pano at NASA APOD Feb. 3, 2014: http://apod.nasa.gov/apod/ap140203.htm

See below our time-lapse photo mosaic showing China’s Yutu rover dramatically trundling across the Moon’s stark gray terrain in the first weeks after she rolled all six wheels onto the desolate lunar plains.

The complete time-lapse mosaic shows Yutu at three different positions trekking around the landing site, and gives a real sense of how it maneuvered around on its 1st Lunar Day.

The 360 degree panoramic mosaic was created by the imaging team of scientists Ken Kremer and Marco Di Lorenzo from images captured by the color camera aboard Chang’e-3 lander and was featured at Astronomy Picture of the Day (APOD) on Feb. 3, 2014.

360-degree time-lapse color panorama from China’s Chang’e-3 lander This 360-degree time-lapse color panorama from China’s Chang’e-3 lander shows the Yutu rover at three different positions during its trek over the Moon’s surface at its landing site from Dec. 15-22, 2013 during the 1st Lunar Day. Credit: CNSA/Chinanews/Ken Kremer/Marco Di Lorenzo – kenkremer.com.  See our Yutu timelapse pano at NASA APOD Feb. 3, 2014: http://apod.nasa.gov/apod/ap140203.htm
360-degree time-lapse color panorama from China’s Chang’e-3 lander This 360-degree time-lapse color panorama from China’s Chang’e-3 lander shows the Yutu rover at three different positions during its trek over the Moon’s surface at its landing site from Dec. 15-22, 2013, during the 1st Lunar Day. Credit: CNSA/Chinanews/Ken Kremer/Marco Di Lorenzo – kenkremer.com. See our Yutu timelapse pano at NASA APOD Feb. 3, 2014: http://apod.nasa.gov/apod/ap140203.htm

China’s space officials are currently evaluating whether they will proceed with launching the Chang’e-4 lunar landing mission in 2016, which was a backup probe to Chang’e-3. Although Yutu was initially successful, it encountered difficulties about a month after rolling onto the surface which prevented it from roving across the surface and accomplishing some of its science objectives.

China is pushing forward with plans to start building a manned space station later this decade and considering whether to launch astronauts to the Moon by the mid 2020s or later.

Meanwhile, as American lunar and planetary missions sit still on the drawing board thanks to visionless US politicians, China continues to forge ahead with no end in sight.

Technicians at work testing the  Chang'e-5T1 return capsule. Credit: China Aerospace Science and Technology Corporation/ Spacechina.com
Technicians at work testing the Chang’e-5T1 return capsule. Credit: China Aerospace Science and Technology Corporation/ Spacechina.com

Stay tuned here for Ken’s continuing Earth and planetary science and human spaceflight news.

Ken Kremer

China’s Lunar Lander Spotted by Orbiting Spacecraft

Not much on the Moon escapes the eyes of NASA’s Lunar Reconnaissance Orbiter, and China’s Chang’e-3 lander and Yutu rover are no exception! The pair touched down on the lunar surface on Dec. 14, and just over a week later on Dec. 25 LRO acquired the image above, showing the lander and the 120-kg (265-lb) “Jade Rabbit” rover at their location near the Moon’s Sinus Iridum region.

The width of the narrow-angle camera image is 576 meters; north is up. LRO was about 150 km (93 miles) from the Chang’e-3 site when the image was acquired.

So how can we be so sure that those bright little specks are actually human-made robots and not just a couple of basaltic boulders? Find out below:

According to School of Earth and Space Exploration professor Mark Robinson’s description on Arizona State University’s LROC blog:

The rover is only about 150 cm wide, yet it shows up in the NAC images for two reasons: the solar panels are very effective at reflecting light so the rover shows up as two bright pixels, and the Sun is setting thus the rover casts a distinct shadow (as does the lander). Since the rover is close to the size of a pixel, how can we be sure we are seeing the rover and not a comparably sized boulder? Fortuitously, the NAC acquired a “before” image of the landing site, with nearly identical lighting, on 30 June 2013. By comparing the before and after landing site images, the LROC team confirmed the position of the lander and rover, and derived accurate map coordinates for the lander (44.1214°N, 340.4884°E, -2640 meters elevation).

Before-and-after LROC images of Chang'e-3's landing site
Before-and-after LROC images of Chang’e-3’s landing site: June 30 vs. Dec. 25, 2013

LRO circles the Moon in a polar orbit at an average altitude of 50 km (31 miles). The LROC instrument contains two narrow-angle camera heads (NACs) providing 0.5-meter/pixel panchromatic images over a 5-km swath, a wide-angle camera head (WAC) providing images at a scale of 100 meters in seven-color bands.

Both the Chang’e-3 lander and Yutu rover are reported to be in good health and performing well. The solar-powered rover went into sleep mode on Dec. 26 to wait out the 14-day lunar night, during which time the temperatures on the lunar surface can drop to -180ºC (-292ºF). Yutu’s radioisotope heat source will keep it from freezing, but it won’t be able to generate power from its solar arrays. (Source)

Read more on ASU’s LROC website, and check out Ken Kremer’s article featuring a video of Yutu’s rollout here.

Image credits: NASA/GSFC/Arizona State University

Make Room at the Moon

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Lunar orbit is getting to be a busy place, with several different countries sending spacecraft to the moon. Currently orbiting the Moon are Japan’s Kaguya (also known as SELENE) spacecraft, which has been sending back 3-D movies of the lunar surface, and China’s Chang-e 1, which will gather information on the Moon’s chemical composition with its various cameras, spectrometers and other scientific equipment. In addition, two new missions to the moon will launch this year: India’s Chandrayaan-1 and NASA’s Lunar Reconnaissance Orbiter.

Chandrayaan, which means “journey to the moon” in Hindi, will study the moon at many wavelengths, from X-ray, visible and near-infrared to microwave. It will orbit the moon at just 100 km above the surface. The mission is scheduled to launch on April 9.

“The low orbit will give us really high resolution data,” says Detlef Koschny, Chandrayaan project scientist. The principal mission objective is to map the Moon’s surface in unprecedented detail. Current lunar maps show detail from 30 – 100 meters across. Chandrayaan will produce maps with a resolution of between 5 and 10 meters across the whole surface of the moon.

The European Space Agency (ESA) is collaborating with Indian Space Research Organization (ISRO) for the Chandrayaan-1 mission. A Compact Imaging X-ray Spectrometer will produce x-ray spectroscopic mapping of the moon, and the Infrared Spectrometer will observe the Moon’s chemical composition. Another ESA instrument is the Sub-keV Atom Reflecting Analyzer, which will study the interaction between electrically charged particles from the solar wind and Moon’s surface.

Eight other instruments complete the suite of science instruments, including a 29-kg landing probe which will be dropped onto the Moon’s surface at the beginning of the mission to conduct investigations.

Meanwhile, the Lunar Reconnaissance Orbiter (LRO) is currently undergoing testing at Goddard Spaceflight Center to get ready for its launch on October 28 of this year. LRO will spend at least a year mapping the surface of the moon. Data from the orbiter will help NASA select safe landing sites for astronauts, identify lunar resources and study how the moon’s environment will affect humans.

Engineers at Goddard are building the orbiter and testing spacecraft components to ready them for the harsh environment of space. After a component or entire subsystem is qualified, it is integrated into the LRO spacecraft. The core suite of avionics for the orbiter is assembled and undergoing system tests.

“This is a major milestone for the mission,” said Craig Tooley, LRO project manager at Goddard. “Our team has been working nearly around the clock to get us to this point. Reaching this milestone keeps us on the path to sending LRO to the moon later this year.”

Once fully integrated, the spacecraft will ship to NASA’s Kennedy Space Center, Florida in August in preparation for launch. The orbiter and the Lunar Crater Observation and Sensing Satellite (LCROSS) will launch aboard an Atlas V rocket. LCROSS will study the poles of the moon to confirm the presence or absence of water ice in a permanently shadowed craters. The trip to the moon for the spacecraft will take approximately four days. The Lunar Reconnaissance Orbiter initially will enter an elliptical orbit, also called the commissioning orbit. Once moved into its final orbit, a circular polar orbit approximately 31 miles above the moon, the spacecraft’s instruments will map the lunar surface.

Original News Sources: Chandrayaan Press Release, LRO press release