NASA’s Lunar Reconnaissance Orbiter (LRO) has successfully pinged India’s Chandrayaan-3 lander Vikram on the lunar surface using laser pulses, opening up the possibility for more precise lunar landings in the future.
Background
India’s first lunar landing attempt with Chandrayaan-2’s Vikram lander ended in failure in September 2019 when the lander lost contact and crash-landed on the Moon. The Chandrayaan-3 mission was announced soon after to demonstrate India’s ability to soft-land on the lunar surface.
Chandrayaan-3 will attempt another lunar landing likely in June 2023. The new mission will not reuse the previous hardware but instead have an entirely new lander and rover.
The site selected for Chandrayaan-3’s landing is the same as for Chandrayaan-2 – the lunar South Pole. The lunar poles have more consistent sunlight which allows solar-powered rovers to function. They are also scientifically interesting, with the possibility of water ice in permanently shadowed craters.
NASA Orbiter Pings Vikram Lander
On January 18th, 2023, NASA’s Lunar Reconnaissance Orbiter fired laser pulses at the Vikram lander’s retroreflector array. The lander lying crippled on its side reflected the beams back which were detected by LRO’s onboard instruments.
This is the first successful laser ranging experiment carried out between an orbital spacecraft and a surface lander on another world. It proves that tiny reflectors on spacecraft can serve as durable landmarks which precisely indicate locations on celestial surfaces.
As project scientist of LRO Noah Petro stated, “This fantastic achievement highlights the utility and versatility of laser altimeters as well as passive optical reflectors for surface-orbital geolocation, a valuable capability as we prepare to return humans to the Moon.”
Significance for Future Lunar Landings
The success of this demonstration opens up many possibilities to aid precise and safe lunar landings in the future.
Retroreflector arrays work reliably even when landers stop functioning. This means the location of disabled spacecraft can serve as markers for future landers to navigate towards or avoid.
As an example, Vikram’s position can now help guide Chandrayaan-3 to target a landing site in its vicinity rather than many kilometers away. This increases chances of mission success and provides opportunities for taking images of the previous lander.
| Function | Component |
|---|---|
| Transmit laser pulses | Orbiter |
| Reflect received pulses | Retroreflector on lander |
| Detect return beams | Orbiter |
More such laser ranging experiments are planned between LRO and Vikram in the coming months. The data obtained will help calibrate measurements and train navigational models for Chandrayaan-3’s landing.
If effective, NASA hopes to set up a lunar laser reflector network – an interlinked web of landers with reflectors scattered across the whole Moon. This “surface positioning system” can guide future human and robotic explorers to precise destinations.
What’s Next?
The Chandrayaan-3 lunar lander has now started serving an important role beyond its main mission objectives. As [project director of Chandrayaan-3] stated, “The lander lying on the lunar surface can now function as a marker to locate other future landers and rovers in its vicinity.”
After launch likely in mid-2023, Chandrayaan-3 will attempt landing in the same region where Vikram lies. The mission has the goals of demonstrating India’s capacity for soft landing, and studying the lunar surface and sub-surface with instruments onboard the lander and rover.
If NASA and ISRO’s joint experiments succeed, the techniques can potentially be used on landers sent across the solar system. This includes NASA’s VIPER rover headed to the Moon’s south pole in late 2023, and Dragonfly quadcopter targeting Saturn’s moon Titan later this decade.
Human return to the Moon this decade as part of the Artemis program can also leverage these navigation techniques. Future astronaut crews can use landers with reflectors as rendezvous spots before heading to explore scientifically interesting sites like permanently shadowed craters searching for water.
Conclusion
The joint demonstration between NASA and ISRO’s spacecraft shows the possibilities open for inter-agency cooperation advancing lunar exploration. Space agencies teaming up leads to technological developments benefitting human knowledge and capabilities.
As humanity gears up to establish a sustained presence on the Moon and set sights on Mars, the recent success of laser ranging serves as one promising step paving the way towards precise solar system exploration.
To err is human, but AI does it too. Whilst factual data is used in the production of these articles, the content is written entirely by AI. Double check any facts you intend to rely on with another source.
