Lunar orbiter Danuri succeeds 1st orbit insertion

The Danuri, Korea's first domestically developed lunar orbiter, has successfully orbited around the moon. The lunar orbiter successfully completed its first orbit insertion (LOI) maneuver and committed itself to the moon's gravity.

The Korea Pathfinder Lunar Orbiter completed an orbit insertion maneuver at 2:45 a.m. Saturday, according to the Korea Aerospace Research Institute (KARI). The LOI maneuver is about reducing the orbiter's speed by using a thruster to settle on an orbit 100 kilometers above the moon.

The KARI analyzed the orbit for two days since the first LOI insertion. It confirmed that the Danuri reduced its speed as planned from 8,000 kilometers per hour to 7,500 kilometers per hour to enter the targeted orbit. The moon orbits the Earth at a speed of about 3,600 kilometers per hour, the speed of a fired bullet. Therefore, it was a challenging yet successful task with a double speed of 7,500 kilometers to 8,000 kilometers per hour. It could have sprung out into the universe if it had not reduced speed enough. It could have collided with the moon if it had reduced its speed too much.

Crossing the seven-minute ridge of the first maneuver, the Danuri will conduct four additional LOI maneuvers until December 28. It's a maneuver that aims to move toward the mission orbit. "We can't let our guard down until the end," an official from KARI said. "The remaining maneuvers are also important."

The final fifth operation is scheduled for Wednesday. After data analysis, on December 29, it will be finally confirmed whether the Danuri succeeded in settling into the lunar mission orbit. If it is successful, it will inspect the initial operation of the payload and function test of the body in January next year. From February, it will perform its main duties, such as receiving scientific observation data or performing technology verification tests.


jawon1212@donga.com