China's lunar probe will reach moon orbit tonight
China's lunar probe, the Chang’e 3, is expected to reach a circular orbit about 100 kilometres above the moon tonight, the Beijing Morning Post reports.
The probe will stay there for about a week, making observations and testing equipment before touching down on the lunar surface and releasing a robotic rover next weekend.
The moon arrival was earlier than scheduled because Chinese space authorities cancelled a routine orbital manoeuvre, according to Xinhua.
They planned to fire the probe's rockets three times to bring it on to the transitional orbit of the moon but the third was no longer necessary after the first two manoeuvres hit their target, authorities said.
The major challenge will be the soft landing.
It is the first time that China has used a rocket engine that can vary its thrust in a space mission.
3D Animation: hello from the Moon
To bring the rover accurately on to the landing spot, the rockets will adjust their thrust dramatically from 1,500 to 7,500 Newton units.
Without atmospheric pressure to slow down the entry, rockets provided the only means to keep the landing vehicle on trajectory and prevent a disastrous crash.
Chinese space authorities said that they had to innovate to reduce the cost of the landing rockets, but were still assured of their quality and reliability. Successful performance testing was carried out on orbits around earth after last weekend’s launch.
The Chang’e 3 has prompted lunar fever on the mainland.
Imitation rovers have been listed on Taobao.com, the largest online shopping platform in China.
One Beijing seller’s six-wheel model claims it can move freely on terrains from office desks to rocky fields
Named the Jade Rabbit Explorer, it is priced at 2,250 yuan (HK$2,866). By noon today it has seen 41 viewers but none have been sold.
Video: Watch China's moon rover blast into space