Chinese space officials announced that their Chang’e-1 spacecraft entered lunar orbit on Monday, completing a new milestone in the country’s goals of space exploration. The spacecraft is scheduled to begin scanning the lunar surface on Wednesday, but first, it has to complete two additional braking maneuvers.
Mission controllers gave the command at 11:15 local time from the Beijing Aerospace Control Center (BACC) for Chang’e-1 to make its braking maneuver – when it was 300 km from the Moon. It completed the maneuver 22 minutes later, entering a true circumlunar orbit.
This braking maneuver was critical. If it braked too early, the probe wouldn’t have been captured by the Moon’s gravity, and it would have drifted off into space. If it braked too late, it would have just crashed onto the lunar surface.
The spacecraft’s speed was slowed from 2.3 km/second to 1.9 km/second. It’s now traveling in a 12-hour elliptical orbit around the Moon, getting as close as 200 km above the surface, and then swinging out to 8,600 km.
Two more braking maneuvers are planned to lower its orbit; one on November 6th, and another on the 7th. When it’s all said and done, Chang’e-1 will be going a mere 1.59 km/second, in a 127-minute orbit. It will then begin its science operations.
If all goes well, Chang’e-1 will provide detailed images and data on the lunar surface. China has announced their plans to send a robotic lander to the Moon by 2012 years, and humans within 15 years.
It should remain in lunar orbit for about a year.
Original Source: Xinhua News Release