A NASA spacecraft has successfully pinged India’s Chandrayaan-3 lander on the moon.
According to NASA, a laser beam was transmitted and reflected between its Lunar Reconnaissance Orbiter (LRO) and the Vikram lander for the first time on the lunar surface.
The US space agency said that this successful experiment opens the door to a new style of precisely locating targets on the moon’s surface.
“At 3 p.m. EST on Dec. 12, 2023, NASA’s LRO pointed its laser altimeter instrument toward Vikram. The lander was 62 miles, or 100 kilometers, away from LRO, near Manzinus crater in the moon’s south pole region, when LRO transmitted laser pulses toward it. After the orbiter registered light that had bounced back from a tiny NASA retroreflector aboard Vikram, NASA scientists knew their technique had finally worked,” NASA stated.
NASA said that sending laser pulses toward an object and measuring how long it takes the light to bounce back is a commonly used way to track the locations of Earth-orbiting satellites from the ground.
“We’ve showed that we can locate our retroreflector on the surface from the moon’s orbit.“
The next step is to improve the technique so that it can become routine for missions that want to use these retroreflectors in the future,” Xiaoli Sun, who led the team at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, that developed the retroreflector on Vikram as part of a partnership between NASA and the Indian Space Research Organisation (ISRO), said in a statement.
Commenting on this development ISRO said that the Laser Retroreflector Array (LRA) Instrument on Chandrayaan-3 lander started serving as a location marker near lunar south pole.
”The LRA on the Chandrayaan-3 lander has begun serving as a fiducial point (precisely located markers for reference) on the moon. NASA’s LRO achieved a laser range measurement using the LRA by successfully detecting signals reflected by it on December 12, 2023,” ISRO said in a statement.
NASA’s LRA was accommodated on the Vikram lander under international collaboration. It comprises eight corner-cube retroreflectors on a hemispherical support structure. This array facilitates lasers ranging from various directions by any orbiting spacecraft with suitable instruments. The passive optical instrument, weighing about 20 grams, is designed to last for decades on the lunar surface.
The Vikram lander landed in the lunar south pole region on August 23, 2023.
ISRO said that while several LRAs have been deployed on the moon since the beginning of lunar exploration, the LRA on Chandrayaan-3 is a miniature version and is the only one available near the south pole currently.
“NASA’s LRA on Chandrayaan-3’s Vikram lander will continue to serve as a long-term geodetic station and a location marker on the lunar surface, benefitting current and future lunar missions,” ISRO said. “These measurements, apart from helping in precise determination of spacecraft’s orbital position, will help refine the lunar geodetic frame, revealing insights into the moon’s dynamics, internal structure, and gravitational anomalies.”
