The Vikram lander of Chandrayaan-3 has solidified its presence as a notable landmark on the Moon. A NASA spacecraft currently orbiting the Moon recently conducted a successful laser beam experiment, directing beams towards a small mirror-based instrument on Vikram. The reflected beams were received, affirming the feasibility of a novel method for precise lunar object localization.
NASA’s Lunar Reconnaissance Orbiter (LRO), in orbit since June 2009, executed the laser experiment on December 12, 2023. However, the results were only disclosed last Friday by both NASA and the Indian Space Research Organisation (ISRO). The laser beams interacted with the Laser Retroreflector Array (LRA), a dome-shaped instrument on Vikram containing eight finely-polished mirrors. These mirrors, strategically oriented, efficiently reflect light from any direction.
The LRA, weighing a mere 20 grams, was specifically placed on Vikram by NASA for this experiment. Notably, this instrument lacks electronics, requiring no power or maintenance, allowing it to remain functional for years or even decades. With this experiment, all seven payloads on Vikram and the two on the Pragyaan rover have been tested and verified to operate as intended.
“We have demonstrated the ability to locate our retroreflector on the Moon’s surface from lunar orbit. The next step is to refine the technique for routine use in future missions utilizing these retroreflectors,” stated Xiaoli Sun, the leader of the LRA instrument development team, according to a NASA statement.
This LRA on Vikram is not the first of its kind on the Moon; similar instruments were deployed by the Apollo missions and are still in use. The LRA on Vikram, being the smallest and most sophisticated, has diverse applications. Positioned near the Moon’s South Pole, it has the potential to guide future lunar missions and serve as a geodetic station.
The NASA statement emphasized the versatility of the new generation of tiny retroreflectors, citing applications ranging from precision markers on the International Space Station to aiding Artemis astronauts during moon landings. ISRO highlighted that the LRA on Vikram is designed to endure for decades, contributing as a long-term geodetic station and a location marker on the lunar surface.
The recent malfunction of a US spacecraft carrying an LRA instrument made by NASA was also mentioned. The spacecraft, launched on January 8, encountered issues during flight, leading to its splashdown into the ocean due to a propellant leak.
Additionally, the Japanese SLIM mission, which landed on the Moon, features a similar instrument. However, the lander is facing challenges with its solar panels, hindering power generation. JAXA has announced that the team will provide an update after analyzing the situation next week.
