a lander on the lunar surface

Chandrayaan-3’s Smooth Lunar Landing: Minimal Moon Dust Raises Scientific Interest

India’s Chandrayaan-3 spacecraft achieved a remarkable feat by landing near the moon’s south pole last August. It managed to do so while creating minimal moon dust disturbance. This was made possible by a special arrangement of its engines, according to a recent study. This innovative approach allowed the spacecraft’s cameras to capture clear images of the landing area. These images were crucial in the final moments before landing, helping to navigate away from dangerous craters and ensuring a safe landing.

Suresh K, a scientist at the Space Applications Centre (SAC) of the Indian Space Research Organisation (ISRO) in Gujarat, India, highlighted the significance of the south pole. He mentioned that the most scientifically valuable areas are also the most hazardous.

During a presentation at the Lunar and Planetary Science Conference (LPSC) in Texas, Suresh K shared insights from the mission. He discussed the pre- and post-landing images captured by the mission, which operated on the moon for two weeks. Unfortunately, the spacecraft was expectedly unable to survive the extreme cold of the lunar night.

The process of landing a spacecraft involves firing engines to slow down for a gentle touchdown. This action typically stirs up a large plume of moon dust. However, Chandrayaan-3’s cameras detected a significantly smaller dust plume, starting just 59 feet above the lunar surface. This is the smallest amount of moon dust disturbance recorded among moon landings, including those by NASA’s Apollo missions and China’s Chang’e-3.

The analysis of the landing site was conducted using images from the Vikram lander and a high-resolution camera on the Chandrayaan-2 orbiter. The dust settled over an area of about 1,561 square feet around the lander. This suggests that the spacecraft displaced a significant amount of lunar regolith, more than previously estimated.

The minimal dust disturbance was attributed to the spacecraft’s lack of a central engine, which resulted in lower engine thrust during descent. The spacecraft began its descent from an orbit of 18.6 miles above the lunar surface. As it approached its landing site, it switched off two of its four engines, relying on the remaining two for the final descent. This approach, using the least powerful engine to date, caused very little disturbance on the lunar surface.

The mission team is still analyzing data regarding the impact of the spacecraft’s mass and the local regolith properties on the dust plume. More findings are expected to be shared in the coming months.

Vikram and Pragyan, the rover, achieved several milestones during their operational period on the moon. The landing site was named Shiv Shakti Point by Indian Prime Minister Narendra Modi, a name awaiting approval by the International Astronomical Union (IAU). The rover traveled 331 feet, detected sulfur, navigated around a dangerous crater, and collected samples from multiple locations.

The mission also included a seismometer on Vikram, which detected moonquakes and micrometeorite impacts. Additionally, a thermal probe was used for the first time to measure the temperature of the lunar soil at various depths.

With Chandrayaan-3’s mission complete, India is already planning its next lunar mission, Chandrayaan-4, scheduled for 2028. This mission aims to bring moon rocks back to Earth. Prime Minister Modi has also expressed the goal of landing an astronaut on the moon by 2040, though specific plans for achieving this are yet to be shared by ISRO and its partner institutions.