{"id":786501,"date":"2024-07-29T13:08:50","date_gmt":"2024-07-29T18:08:50","guid":{"rendered":"http:\/\/spaceweekly.com\/?p=786501"},"modified":"2024-07-29T13:08:50","modified_gmt":"2024-07-29T18:08:50","slug":"nasa-jaxa-bounce-laser-beam-between-moons-surface-and-lunar-orbit","status":"publish","type":"post","link":"https:\/\/spaceweekly.com\/?p=786501","title":{"rendered":"NASA, JAXA Bounce Laser Beam Between Moon\u2019s Surface and Lunar Orbit"},"content":{"rendered":"


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NASA\u2019s LRO (Lunar Reconnaissance Orbiter) has twice transmitted a laser pulse to a cookie-sized retroreflector aboard JAXA\u2019s (Japan Aerospace Exploration Agency) SLIM lander on the Moon and received a return signal.<\/p>\n

As LRO passed 44 miles above SLIM (Smart Lander for Investigating Moon) during two successive orbits on May 24, 2024, it pinged the lander with its laser altimeter instrument as it had done eight times before. But, on these two attempts, the signal bounced back to LRO\u2019s detector.<\/p>\n

This was an important accomplishment for NASA because the device is not in an optimal position. Retroreflectors are typically secured to the top of landers, giving LRO a 120-degree range of angles to aim toward when sending laser pulses to the approximate location of a retroreflector. However, the SLIM lander had settled on the surface with its top facing sideways, limiting LRO\u2019s range.<\/p>\n

To boost the chances of reaching their target, the LRO team worked with JAXA to determine the exact location and orientation of SLIM. Then, NASA engineers predicted when LRO\u2019s orbit trajectory would bring it to coordinates that would give it the best chance of reaching SLIM\u2019s retroreflector with the laser beams.<\/p>\n

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SLIM on the lunar surface captured by the LEV-2 (SORA-Q) rover. <\/div>\n<\/figcaption><\/div>\n<\/div>\n<\/div>\n

\u201cLRO\u2019s altimeter wasn\u2019t built for this type of application, so the chances of pinpointing a tiny retroreflector on the Moon\u2019s surface are already low,\u201d said Xiaoli Sun, who led the team that built SLIM\u2019s retroreflector at NASA\u2019s Goddard Space Flight Center in Greenbelt, Maryland, as part of a partnership between NASA and JAXA.<\/p>\n

\u201cFor the LRO team to have reached a retroreflector that faces sideways, instead of the sky, shows that these little devices are incredibly resilient,\u201d Sun said.<\/p>\n

SLIM touched down on the Moon\u2019s surface on Jan. 20. The retroreflector that hitched a ride with the lander, called a Laser Retroreflector Array, is one of the six NASA has sent to the Moon aboard private and public landers, and the second to bounce signal back to LRO\u2019s altimeter.<\/p>\n

The first time a laser beam was transmitted from LRO to a NASA retroreflector and back was on Dec. 12, 2023, when LRO pinged ISRO\u2019s (Indian Space Research Organisation) Vikram lander. LRO has since exchanged laser pings with Vikram three more times.<\/p>\n

NASA\u2019s retroreflector has eight quartz corner-cube prisms set into a dome-shaped aluminum frame that is 2 inches wide. With no power or maintenance required, retroreflectors can last on the Moon\u2019s surface for decades and thus provide reliable beacons for future missions.<\/p>\n

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NASA\u2019s Laser Retroreflector Array installed on JAXA\u2019s SLIM lander before launch. <\/div>\n<\/figcaption><\/div>\n<\/div>\n<\/div>\n

The retroreflectors could guide Artemis astronauts to the surface in the dark, for example, or mark the locations of spacecraft already on the surface to help astronauts and uncrewed spacecraft land near them.<\/p>\n

LRO\u2019s laser altimeter, the only laser instrument orbiting the Moon for now, was designed to map the Moon\u2019s topography to prepare for missions to the surface \u2014 not to point to within 1\/100th of a degree of a retroreflector, which is what LRO engineers are trying to do with every ping.<\/p>\n

LRO is managed by NASA\u2019s Goddard Space Flight Center in Greenbelt, Maryland, for the Science Mission Directorate at NASA Headquarters in Washington. Launched on June 18, 2009, LRO has collected a treasure trove of data with its seven powerful instruments, making an invaluable contribution to our knowledge about the Moon. NASA is returning to the Moon with commercial and international partners to expand human presence in space and bring back new knowledge and opportunities.<\/em><\/p>\n

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\n\t\tNASA\u2019s LRO Spots Japan\u2019s Moon Lander\u00a0<\/span><\/p>\n<\/div>\n
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\n\t\tNASA\/JAXA\u2019s XRISM Mission Captures Unmatched Data With Just 36 Pixels<\/span><\/p>\n<\/div>\n


<\/strong>By Lonnie Shekhtman
NASA\u2019s Goddard Space Flight Center, Greenbelt, Md.\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0<\/strong>\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0
\u00a0
Media Contact:
Nancy Neal Jones
NASA\u2019s Goddard Space Flight Center, Greenbelt, Md.<\/strong><\/em><\/p>\n

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