Chang'e-3 (Yutu)

Launch data: Designation  39458 / 13070A Launch date  01 Dec 2013 - 17:30 UT Launch site  Xichang, LC-2 Launch vehicle  CZ-3B/G3Z Mission  Lunar lander and rover Heliocentric orbit Perihelion / Aphelion   A.U. Eccentricity   Inclination   deg Period   min

Artists concept of the Chinese Chang´e 3 lander and rover on the lunar surface (image credit: Beijing Institute of Spacecraft System Engineering)

Spacecraft data: Prime manufactor  CAST Platform   Operator   Mass at launch  3780 kg (launch); 1200 kg (lander); 120 kg (rover) Dry Mass   kg Basic shape   Dimensions (m)   Solar array  2 deployable solar arrays (on lander and on rover) Stabilization   DC power   Landing date on Moon  14 Dec 2013 - 13:11:18 UT Landing location  19.51W 44.12N

Photo of the lunar rover in a field test

Description:

• Chang'e 3 is China's first lunar lander project, which consists of a lander module, which will deploy the solar powered Yutu rover on the lunar surface.
• CHANG'E 3 is a lunar landing mission, the third Chinese lunar probe following a pair of orbiters launched in 2007 and 2010. The lander carries a bipropellant rocket engine designed to adjust its power level and pivot to control the probe's descent from an altitude of 15 kilometers, or about 9 miles. The probe is equipped with terrain recognition sensors to feed data into the lander's computer, which can autonomously guide the spacecraft to a flat landing zone clear of boulders, craters and steep inclines. That's a first for an unmanned mission, and all robotic landers up to now had to risk settling on to rock fields or other unwelcoming terrain, including NASA's Curiosity rover when it touched down on Mars. The rover has a mass of 140 kilograms, or about 308 pounds, and carries radioisotope heater units to keep the spacecraft warm during the two week-long lunar nights. The heaters are likely powered by small quantities of plutonium-238, the isotope of plutonium preferred for space missions. The Yutu rover carries advanced radars to study the structure of the lunar crust at shallow depths along its path, and it is outfitted with spectrometers to detect the elements making up the moon's soil and rocks. Four navigation and panoramic cameras are mounted on the rover to return high-resolution images from the moon.

Mission details:

• China´s most ambitious lunar mission began on Dec 1, 2013 with the launch of the Chang´e-3 spacecraft from Xichang into a 210 x 389109 km x 28.5 deg lunar transfer orbit. On Dec 6 at 09:50 the spacecraft entered a 100 km polar orbit around the Moon.
• The heavy (3800 kg wet, 1200 kg at landing) spacecraft has a descent engine and landing legs, and has a variety of lunar surface science experiments. It also carries Yutu, a small 140 kg rover.
  
  

  Cruise profile of the Chang'e-3 mission (image credit: Beijing Institute of Spacecraft System Engineering,

  
  
• Chang´e-3 was in lunar polar orbit from Dec 6 to Dec 14, 2013. On Dec 10 at 1320 UTC the orbit was lowered from 100 x 100 to 15 x 100 km. At 1259:52 UTC Dec 14, near perilune, the descent engine was turned on to decelerate the probe and fly it down to the surface. Chang´e-3 touched down at 1311:18 UTC Dec 14, at 19.51W 44.12N, about 43 km south of crater Laplace F in the Mare Imbrium. This was the first lunar soft landing since the USSR's Luna-24 in 1976.
  • Note: The original planned landing site was in Sinus Iridum (Bay of Rainbows) but the Chinese decided to land one orbit early, with the probe flying a little further east over Mare Imbrium (Sea of Rains).
  
  
  
• At 2035 UTC on Dec 14 the `Yutu hao' (`rabbit') rover drove down the Chang´e-3 ramp onto the lunar surface. Yutu and Chang´e-3 are both solar powered, but also carry small Pu-238 radioactive heater units to keep systems from freezing during the 14-day lunar night. Yutu has six wheels and a mass of around 140 kg.
• The CZ-3B third stage rocket was launched to a 311 x 352280 km x 29.6 deg orbit which passed close to the Moon at around 1100 UTC on Dec 6 and, according to tracking by astronomers, is currently in a 106000 x 662000 km x 35.8 deg orbit around the Earth-Moon system.
  
  

  Photo of the Yutu rover taken by the Chang´e-3 lander on the moon on Dec. 15, 2013 (image credit: BACC, CAS)

  Photo of the Chang´e-3 lander taken by the rover Yutu on the moon on Dec. 15, 2013 (image credit: BACC, CAS)

  
  
  
  

  Chang´e-3 panorama picture of moon

  
  

External links:

• Spaceflight 101: Chang´e Information
• EOportal.org Satellite description

Astrophilately covers:

Launch cancel '2013 12 02' - Credit: #410

Change 3 in orbit around the Moon. Credit: #411a