Danuri Mission Duration Officially Extended by 2 More Years

Ministry of Science and ICT and KAIST Space Center to Hold Lunar Exploration Promotion Committee Meeting on the 27th for Finalization

The mission operation period of Danuri, South Korea's first lunar exploration orbiter, has been officially extended.

The Ministry of Science and ICT and the Korea Aerospace Research Institute (KARI) held the 'Lunar Exploration Project Promotion Committee' on the 27th and extended Danuri's mission operation period from the originally planned one year to three years. Danuri, which officially started its mission in January this year, was scheduled to operate for one year until the end of December. With this decision, it will be operated for an additional two years until December 2025.

The reason for extending Danuri's mission period is that it conserved fuel during the journey to the Moon. Launched in August last year, Danuri did not choose the 'direct transfer orbit,' which goes straight from Earth to the Moon in 3 to 4 days but consumes a tremendous amount of fuel during deceleration. Instead, it selected the ballistic lunar transfer orbit (BLT), which first heads toward the Sun and then returns to join the lunar orbit. Although it takes more than four months, this method minimizes fuel consumption and maximizes the orbiter's operational period. In particular, about 30 kg of fuel was saved through successful launch, control, and navigation during the Earth-Moon transfer process. While up to 202.64 kg of fuel consumption was expected, only 172.92 kg was actually used. The lunar orbiter must periodically inject fuel to maintain altitude; if it runs out, it will fall to the Moon due to gravity and end its lifespan.

KARI analyzed Danuri's remaining fuel and the impact on its main components to confirm the possibility of extending the mission period. As a result, it was judged that extended operation until 2025 is feasible. After entering the mission orbit, Danuri's remaining fuel (as of December 27 last year) was about 86 kg, and considering the annual fuel consumption of about 26 to 30 kg, a two-year mission extension is expected to be possible.

The main components are also expected to have no operational problems during the mission extension except for a reduction in daily mission time in 2025 when the solar panels and batteries will age. However, two total lunar eclipses (March 14 and September 7, 2025) are expected, which may cause early termination of the mission due to battery discharge. The power generated by the solar panels and battery capacity gradually decrease over time. KARI expects that Danuri will be able to operate all day in 2023 and 2024 but will only be able to perform missions for up to 16 hours per day in 2025.

On this day, the committee reviewed and approved the 'Extension of the Lunar Orbiter Danuri Mission Operation Period and Future Operation Plan (draft),' extending Danuri's mission operation period by two years. Danuri will carry out its originally planned missions such as searching for lunar landing candidate sites, lunar scientific research, and space internet technology verification until the end of this year, and from next year for two years, it plans to expand the video acquisition area and conduct supplementary observations and additional verification tests.

The exploration data acquired through Danuri's mission operation will be used to produce 3D terrain images of lunar landing candidate sites and maps of lunar surface elements and resources by 2026. It will also be used by domestic researchers to conduct creative convergence research. Furthermore, a space exploration data system capable of efficiently managing and analyzing data generated during space exploration of the Moon, Mars, asteroids, and other celestial bodies will be established by 2026.

Cho Sunghak, Director of the Large Public Research Policy Division at the Ministry of Science and ICT, said, “Through this extension of the mission operation period, we hope that Danuri will fully enjoy the Moon as its name implies. We ask for the public’s great interest and support so that Danuri can carry out its mission smoothly during the extended period.”

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