Danuri Cruises Smoothly... Releases Directly Captured Earth and Moon Photos [Reading Science]

Ministry of Science and ICT-KARI to Conduct Orbital Maneuver on 2nd
"Scheduled to Turn from Sun Direction to Earth Direction"

Earth photographed during navigation by Danuri, Korea's lunar exploration orbiter launched on August 5. Photo by Ministry of Science and ICT

[Asia Economy Reporter Kim Bong-su] South Korea's first lunar orbiter 'Danuri' (KPLO), launched on the 5th, is cruising smoothly. After moving away from Earth and completing a smooth voyage, it reached the scheduled point and performed a maneuver to change its direction back toward Earth.

The Korea Aerospace Research Institute (KARI) announced on the 1st that Danuri will perform a Trajectory Correction Maneuver (TCM) at around 2 p.m. on the 2nd, approximately 1.36 million km away from Earth. TCM is a process of adjusting direction, attitude, and speed using thrusters. Since its launch on the 5th, Danuri has been traveling toward the sun and is currently near the Lagrange Point 1, where the gravitational forces between Earth and the sun balance. This will be the second TCM. The first TCM was conducted on the 7th of last month, two days after launch, to correct errors caused by separation from the launch vehicle. The command was sent in advance in the morning and automatically executed at 2 p.m. KARI plans to observe the trajectory for about 48 hours before determining the success of the maneuver.

Earth and the Moon photographed during navigation by Danuri, Korea's lunar exploration orbiter launched on August 5. Photo by Ministry of Science and ICT

The Ministry of Science and ICT plans to announce the success of the trajectory correction in the afternoon of the 4th. If there is an error, another TCM will be conducted on the 16th. Danuri's trajectory is being tracked in real-time by the deep space ground antenna installed in Yeoju, South Korea during the day, and by the deep space ground antennas in Madrid, Spain, and Goldstone, Los Angeles, USA at night.

In this regard, the Ministry of Science and ICT and KARI received and released photos taken by Danuri of Earth on the same afternoon.

The Moon photographed by Danuri, Korea's lunar exploration orbiter launched on August 5. Photo by Ministry of Science and ICT

There are still challenges ahead. If the second TCM is successful, Danuri will reverse its direction and use Earth's gravity to travel to the moon. From launch until mid-December, it will travel a total of 6 million km over four and a half months to reach lunar orbit. Even if this maneuver succeeds, a retrograde maneuver to reduce speed near lunar orbit will be necessary. Additionally, a Lunar Orbit Insertion (LOI) maneuver will be conducted to be captured by the moon's gravity. Danuri is scheduled to enter lunar orbit on December 17, with the target arrival at an altitude of 100 km set for January 1 of next year.

Danuri's complex maneuvers are due to its choice of a ballistic lunar transfer (BLT) trajectory to conserve fuel. Unlike the direct transfer (3 days) that goes straight to the moon or the phasing transfer (30 days) that orbits Earth extensively before being captured by lunar gravity, this method takes longer but saves more than 20% of fuel, thereby extending the mission duration of the probe.

Meanwhile, Danuri is equipped with six scientific instruments, including NASA's permanently shadowed region camera (ShadowCam), Korea's self-developed wide-field polarization camera, gamma-ray and magnetometer sensors, a high-resolution camera, and space internet equipment. It will carry out missions for about one year, such as searching for landing candidate sites by detecting the presence of ice at the lunar south pole and terrain, as well as geological, topographical, and resource exploration.

This content was produced with the assistance of AI translation services.