‘The Ministry of Science and ICT’ and the ‘Korea Aerospace Research Institute’ announced that Danuri, the lunar orbiter, will launch the first lunar orbit entry maneuver to enter the lunar orbit at 2:45 A.M. on December 17, 2022.
Danuri flew a total of 5.94 million kilometers (accumulated) along the Earth-Moon transition trajectory for about 4.5 months after its launch on August 5,approaching the distance of about 108 kilometers from the moon on December 17. Afterwards, Danuri will land on the moon's mission orbit (100km above the moon) after five mission orbit entry maneuvers from December 17 to December 28.
In particular, the first entry maneuver is the most important one to ensure that Danuri is stably captured by the moon's gravity and does not pass by the moon. During this process, the thrusters shall be operated for approximately 13 minutes to decelerate the Danuri’s speed from about 8,000 km/h to 7,500 km/h. It should be placed accurately to the target position at the same time.
This is a high-level task that involves entering a faster-moving Danuri into the lunar orbit, which marks speed of the bullet (about 3,600 km/h). The results of the first entry maneuver will be derived on December 19 after data analysis.
After the second to fifth entry maneuvers (12.21-12.28), it will be confirmed whether Danuri will succeed in settling the lunar mission orbit on December 29.