Chang'E-1 has blazed a new trail in China's deep space exploration

Dec 01, 2009
This is a lunar global topographic map with a grid size of 0.0625o×0.0625o based on the CE-1 lunar DEM model CLTM-s01. In Lambert Azimuthal Equal-Area projection, the left is the far side with centric longitude of 180oE and the right is the near side with central longitude of 0oE. The new topographic characteristics (highlighted by black circles in the figure) discovered by the CE-1 laser are the impact basin Fitzgerald-Jackson (25oN, 191oE) and the impact crater Wugang (13oN, 189oE) on the far side, and the volcanic deposit highland Yutu (14oN, 308oE) on the near side. Credit: Science in China Press

A huge amount of scientific data have been accumulated by the CE-1 lunar orbiter. Using laser altimeter data, Jinsong Ping and Qian Huang et al obtained improved 3D lunar topography, and based on this, they had made new discoveries (such as impact basins and volcanic deposit highlands) of some ancient topographic characteristics on the lunar surface. Chao Chen and Qing Liang et al found the South Pole-Aitken (SPA) basin as the biggest mascon on the moon and put forward a fault structure hypothesis for the Apenninue Mountain, which is significant for the study of the origin and evolution of the moon.

The above special-issue papers reporting on the Chang'E selenodesy results were jointly accomplished by experts from the Shanghai (SHAO), the China University of Geosciences (Wuhan) and other institutions. They will appear on Vol. 39 Issue 10 of the "Science in China Series G: Physics, Mechanics & Astronomy" and Vol. 54 Issue 20 of the Chinese Science Bulletin.

Since the 1990s, there has been a new worldwide upsurge of lunar exploration missions. As did the other lunar spacecrafts launched about the same time frame, the CE-1 lunar orbiter focused on selenodesy so that it could remedy the low resolution and poor coverage problems of past data, and would open the door to recovering lunar evolution by detecting new lunar topography, gravity fields or interior structures. Furthermore, it would prepare for future Chinese spacecraft landing on the surface of the moon.

Lunar topography, chemical composition and thickness all show obvious dichotomy. In-depth investigation into the lunar dichotomy and characteristics of basins, mascons, impact craters and volcanic highlands is the only way to throw light on the history of lunar evolution. Based on the CE-1 lunar DEM model CLTM-s01 published in 2008, researchers from SHAO took a comparative planetary science approach and successfully found some impact basins (i.e. the quasi-impact basin Sternfeld-Lewis and impact basin—Fitzgerald-Jackson) and one crater (i.e. the crater-Wugang) on the far side, and one middle scale volcanic deposit highland (i.e. the 2.8 km highland-Yutu) on the nearside. Moreover, they analyzed and identified some middle scale impact basins and classified them according to their circular characteristics. Based on the Bouguer gravity anomaly, researchers from the China University of Geosciences confirmed that the South Pole-Aitken (SPA) basin is the biggest mascon on the terrestrial planets in the solar system. Comparing the Apenninue Mountain of the moon with the Himalayas on the earth, they put forward a hypothesis about the possible existence of a big fault structure band, which would possibly change our previous knowledge that there is no motion in the interior of the moon.

Due to certain operational limitations, it is difficult to calibrate the data collected by the CE-1 orbiter. The researchers tried to get around various problems with novel techniques (especially related to the interferometer spectrometer imager), and made the previously inapplicable data useful for estimating the distribution of lunar materials. Besides, Chinese astronomers creatively monitored the critical arcs of the CE-1 trajectory with a VLBI measurement platform. As forward-looking technologists, they also performed open-loop radiometric tracking of the spacecraft and other unprecedented test experiments, while further participating in same-beam observation of the Japanese SELENE spacecrafts. We believe these pioneering works would make a significant contribution to our country's future deep space exploration.

Source: Science in Press

Explore further: SDO captures images of two mid-level flares

add to favorites email to friend print save as pdf

Related Stories

SMART-1 diagnoses wrinkles and excess weight on the Moon

Aug 22, 2007

Owing to SMART-1’s high resolution and favourable illumination conditions during the satellite’s scientific operations, data from Europe’s lunar orbiter is helping put together a story linking geological ...

SMART-1: Europe on the Moon, 1 year on

Aug 31, 2007

A year ago, as Europe reached the Moon for the first time, scientists on Earth eagerly watched SMART-1’s spectacular impact. New results from the impact analysis and from the instruments still keep coming.

Recommended for you

SDO captures images of two mid-level flares

Dec 19, 2014

The sun emitted a mid-level flare on Dec. 18, 2014, at 4:58 p.m. EST. NASA's Solar Dynamics Observatory, which watches the sun constantly, captured an image of the event. Solar flares are powerful bursts ...

Why is Venus so horrible?

Dec 19, 2014

Venus sucks. Seriously, it's the worst. The global temperature is as hot as an oven, the atmospheric pressure is 90 times Earth, and it rains sulfuric acid. Every part of the surface of Venus would kill you ...

Image: Christmas wrapping the Sentinel-3A antenna

Dec 19, 2014

The moment a team of technicians, gowned like hospital surgeons, wraps the Sentinel-3A radar altimeter in multilayer insulation to protect it from the temperature extremes found in Earth orbit.

Video: Flying over Becquerel

Dec 19, 2014

This latest release from the camera on ESA's Mars Express is a simulated flight over the Becquerel crater, showing large-scale deposits of sedimentary material.

Spinning up a dust devil on Mars

Dec 19, 2014

Spinning up a dust devil in the thin air of Mars requires a stronger updraft than is needed to create a similar vortex on Earth, according to research at The University of Alabama in Huntsville (UAH).

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.