bodyType

customContents

entityId

entityUuid

articlePageQuery

filter

article

articleBaseAdvertisingInfoArticle

articleListArticle

articleSeoArticle

helpersCheckIsPostiesArticle

hooksArticleAcknowledgementGateOverlayArticle

hooksTrackPageViewArticle

hooksContentInterestArticle

articleLinkingDataContent

articleSchemaContent

liveArticle

advertZone

sentiment

contentLock

topics

types

sections

moreOnThisArticles

urlAlias

commentCount

sponsorType

authorLocations

authors

paywallTypes

corrections

displaySlideShow

multimediaEmbed

printHeadline

seriesContainer

socialHeadline

headline

flag

firstTopic

glossary

flattenTypeIds

publishedDate

additionalInfoBoxes

images

image

relatedLinks

relatedNewsletters

__typename

createdDate

sponsor

factSheets

series

knowledgeQuestion

disableOffPlatformContent

published

updatedDate

summary

subHeadline

body

keywords

copyrighted

customTimezone

liveContents

Alice Shen

Chang’e 4, China’s lunar lander, began tuning in to the oldest and faintest voices from across the universe using the antennas it carried to the “quiet” far side of the moon.
The three five-metre long antennas have opened a new chapter in radio astronomy by picking up low-frequency waves that devices on Earth cannot, as such signals blocked by the planet’s atmosphere.
The lander could help reveal what the universe was like right after the Big Bang, which scientists believe took place about 14 billion years ago.
Back then, low-frequency radio waves were generated as the first stars and galaxies were formed, astronomers said.


“The far side of the moon is very quiet as there are no noises from artificial satellites,” Zou Yongliao, deputy director of China’s National Space Science Centre, told Science and Technology Daily, the official newspaper of the Ministry of Science and Technology.
“Detecting low-frequency radio waves [from] there is a dream of astronomers across the world. It will fill the gap of low-frequency radio observation.”
Another set of those antennas – a kind jointly developed by China and the Netherlands – is carried on the relay satellite Queqiao, which stands between with the Earth and moon.

Astronomers say the far side of the moon is an ideal place to pick up low-frequency radio waves. The United States, Japan and the European Space Agency all made proposals to put a detector there, but China got there first.
“The far side of the moon is the best place in the inner solar system to monitor low-frequency radio waves – the only way to detect certain faint ‘fingerprints’ that the Big Bang left on the cosmos,” Joseph Silk, professor of astronomy at Johns Hopkins University in the US, said in the scientific journal Nature earlier last year, when the US, Europe and China all detailed their plans for missions to the moon.
The fuel quest that could be driving China’s mission to the moon
Radio telescopes on Earth encounter too much interference from electromagnetic pollution caused by artificial signals, such as maritime communications and short wave (high-frequency) broadcasts, to get a clear signal from outside the atmosphere. The Earth’s ionosphere also blocks the longest wavelengths – which have the shortest frequencies – from reaching these devices in the first place.
China and the Netherlands decided to work together to develop the antennas for low-frequency celestial waves in 2015, with the latter focusing on those of Queqiao and China on Chang’e 4.
The cooperation between the two nations began a year after a trade mission when Chinese President Xi Jinping and Dutch King Willem-Alexander met in Amsterdam.

Both sets of antennas were designed to work for years. Powered by solar panels, they could be operating long after the three-year Chang’e 4 mission ends, Ping Jinsong, chief scientist of the radio wave project and a researcher with China’s National Astronomical Observatories, said.
These antennas were also designed to capture a part of the spectrum of the sun’s light that had not been observed before, providing information in predicting solar storms that might threaten the earth, Ping said.
Noise generated by the spacecraft is a major challenge for the antennas attached to Chang’e 4 and its relay. China and the Netherlands came up with different solutions to this problem.
From moon landing to AI, the year ahead in Chinese science
China installed a fourth, shorter antenna on the moon lander. Ping said it would pick up waves from the spacecraft and “subtract” them from the data sent back to Earth.
The Dutch device – developed by the Netherlands Institute for Radio Astronomy and Radboud University – is designed to emit less noise than similar satellites, allowing it to pick up a broader range of radio waves.
“Every discovery made by these radio wave receivers on Chang’e 4 could complement what we know about the very early universe,” Ping said.
Last week, Chang’e 4 sent its lunar rover, Yutu 2, to begin mapping the moon’s inner structures and analysing soil and rock samples.


Magnetic shield over North America is losing strength ‘exceptionally fast’: PLA scientists

Stem cell study could bring hope to women struggling with fertility

Chinese scientists propose ram-rotor detonation engine for hypersonic flight

China’s Mars rover Zhurong finds evidence of ancient ocean on red planet

Science

Listening to the Big Bang: China’s lunar lander tunes in to ancient radio signals from across universe

(190103) -- BEIJING, Jan. 3, 2019 (Xinhua) -- Technicians work at the Beijing Aerospace Control Center (BACC) in Beijing, capital of China, Jan. 3, 2019. China's Chang'e-4 probe touched down on the far side of the moon Thursday, becoming the first spacecraft soft-landing on the moon's uncharted side never visible from Earth. The probe, comprising a lander and a rover, landed at the preselected landing area on the far side of the moon at 10:26 a.m. Beijing Time (0226 GMT), the China National Space Administration announced. (Xinhua/Jin Liwang)

(190103) -- BEIJING, Jan. 3, 2019 (Xinhua) -- A simulated landing process of Chang'e-4 lunar probe is seen through the monitor at Beijing Aerospace Control Center in Beijing, capital of China, Jan. 3, 2019. China's Chang'e-4 probe touched down on the far side of the moon Thursday, becoming the first spacecraft soft-landing on the moon's uncharted side never visible from Earth. The probe, comprising a lander and a rover, landed at the preselected landing area on the far side of the moon at 10:26 a.m. Beijing Time (0226 GMT), the China National Space Administration announced. (Xinhua/Jin Liwang)

China's rover Yutu-2 leaves the Chang'e 4 lander and ventures across the far side of the moon to begin analysing rock samples. The mothership’s mission to scan for radio waves is just beginning. Photo: Reuters

News

China

Chang’e 4 uses its unique position on the ‘quiet’ side of the moon to seek out energy emissions that originated at the time the universe was born


Chang’e 4 uses its unique position on the ‘quiet’ side of the moon to seek out energy emissions that originated at the time the universe was born.
