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A moon expedition has discovered its unsuccessful predecessors.


A spacecraft with solar panels extending off one side flies over the dark surface of the Moon with Earth in the background.

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On 23 August, India’s Chandrayaan-3 mission landed a spacecraft near the south pole of the Moon. The lander, Vikram, and an accompanying rover collected valuable data from the lunar surface for nearly 2 weeks until they were powered down to wait out the lunar night. (Engineers have been trying to reestablish contact since 22 September.)

However, there was no guarantee of the success of the Chandrayaan-3 mission. Only a few days prior, Russia’s Luna-25 spacecraft had failed to land in the same area. In reality, there have been multiple unsuccessful lunar missions recently.

In order to gain a deeper understanding of potential mishaps during a lunar expedition, both scientists and the general public have thoroughly examined data gathered by NASA’s Lunar Reconnaissance Orbiter (LRO) to identify the exact areas of recent crashes. They have identified clear indications of multiple spacecraft making rough landings on our closest celestial body.

All of the Moon, Every Month

Since 2009, the Lunar Reconnaissance Orbiter has been providing a wealth of information on the Moon’s terrain, composition, and water sources. The spacecraft, which is about the size of a truck, is currently orbiting at a distance of approximately 100 kilometers from the Moon’s surface. The Lunar Reconnaissance Orbiter Camera, which includes two Narrow Angle Cameras and one Wide Angle Camera, captures images of most of the lunar surface on a monthly basis.

According to Robert Wagner, a planetary geologist and member of the LRO team, the data gathered by the Narrow Angle Cameras is extremely useful for detecting even the smallest changes in the Moon’s terrain over a period of time. He also noted that these cameras provide the highest-resolution images of the Moon’s surface ever obtained from an orbit, with each pixel representing approximately 50 centimeters.

The data captured by the Lunar Reconnaissance Orbiter Camera is not limited to use by only professional scientists. Every 90 days, a large amount of new data is made available to the public. As of September 15th, the 55th data release has occurred. Nick Estes, the Science Operations Center manager for the Lunar Reconnaissance Orbiter Camera at Arizona State University in Phoenix, stated that there are typically thousands of unique users accessing the observations each month. He also mentioned that the data is actively being utilized.

Shanmuga Subramanian, a mechanical engineer from Chennai, India and a space enthusiast, is an individual who fits this description. In 2019, Subramanian discovered that India’s space organization had lost communication with a previous Vikram. The lander, which was approximately the size of a desk, was originally intended to land on the Moon as part of the Chandrayaan-2 mission. With his experience in coding and knowledge of the high-resolution images of the Moon’s surface taken by the LRO, Subramanian proposed the possibility of using this data to determine the exact location of Vikram’s crash site.

A Meticulous Search

“At least six people in the office were sorting through a large stack of before-after blink images that I had created.”

Subramanian retrieved a photograph captured by the LRO on September 17, 2019, 10 days after Vikram’s alleged collision. He examined it alongside images of the identical area captured in previous months. Subramanian was searching for subtle alterations in the 2- × 2-kilometer images that could potentially indicate remnants of the 600-kilogram lander or a crater caused by its impact. He described the process as time-consuming, stating, “I began examining each individual pixel.”

Image of the Moon’s surface with a lighter circle in center
Combined before and after images from the Lunar Reconnaissance Orbiter show a halo of disturbed soil on the Moon’s surface around the dark impact site. Credit: NASA/Goddard/Arizona State University

However, his thorough investigation proved to be fruitful: After approximately 2 days of searching, Subramanian discovered one unusually bright pixel in the image taken on September 17th that was noticeably absent in previous images. “It was a minuscule white spot,” Subramanian stated. He promptly informed the LRO team, who began searching in the same area. Wagner, who often assists with processing LRO data, gathered pairs of images taken before and after Vikram’s crash and enlisted the help of his colleagues. “We had at least six individuals in the office meticulously examining a large collection of before-and-after images I had compiled,” Wagner explained.

The group verified Subramanian’s finding and recognized over 10 more fragments scattered across approximately 5 square kilometers. Wagner noted that Subramanian’s information was crucial in locating Vikram and the engineering expert was properly acknowledged in NASA’s statement announcing the sighting of the lander.

Are you missing the Lander? Contact LRO for assistance.

Data from the Lunar Reconnaissance Orbiter Camera has also exposed the ultimate resting locations of other disabled spacecraft.

On April 11, 2019, Israel’s Beresheet lander was trying to land in the Sea of Serenity. However, the mission’s command center in Yehud lost communication with the spacecraft. 11 days later, images from the LRO revealed the crash site. The pictures indicated that the lander, about the size of a washing machine, had hit the edge of a small crater and dug up a 100-meter-long area of lunar soil in a rough landing.

Before and after images of the lunar surface

The location where Israel’s Beresheet lander landed was observed by the Lunar Reconnaissance Orbiter. Image credit: NASA/GSFC/Arizona State University

In the beginning of this year, the Hakuto-R Mission 1 lander from Japan experienced a crash on the Moon. The lander was created and constructed by the company ispace and would have been the initial privately-owned spacecraft to successfully land on the Moon. On April 26th, just one day after Tokyo’s mission control lost contact with the lander, the LRO team captured multiple images of the intended landing site near Atlas crater. The team compared these images to previous data and identified approximately four fragments of debris scattered across a 50- × 100-meter area.

Before and after images of the lunar surface
Letters and arrows highlight visible surface changes on the Moon imaged by the Lunar Reconnaissance Orbiter after the Hakuto-R Mission 1 lander crash. Credit: NASA’s Goddard Space Flight Center/Arizona State University

On August 19, when Russia’s Luna-25 made contact with the Moon, just a few days prior to the successful landing of Chandrayaan-3, LRO was once again instrumental in identifying the exact crash location. The manager of the Science Operations Center, Estes, observed a new impact-like feature in the data collected 5 days after the crash. This feature caught his attention without needing to compare it to previous images. He stated, “I saw something that seemed reasonable.”

Before and after images of the lunar surface

NASA’s Goddard Space Flight Center and Arizona State University have released images from the Lunar Reconnaissance Orbiter that reveal a new impact site believed to be caused by Russia’s Luna-25 lander.

The discovery made by Estes was later confirmed by the LRO team, who also concluded that Luna-25 had crashed about 400 kilometers from its original landing location. This resulted in a 10-meter wide crater, which appeared as a brighter spot in LRO data. According to Wagner, the change in brightness was quite remarkable and became more apparent when comparing images before and after the impact. The images revealed a spray pattern of ejecta.

The LRO has been collecting data for 14 years and now has over a petabyte of observations and metadata, according to Estes. Recently, NASA launched an interactive app that showcases LRO data. This allows scientists and the general public to compare observations of the Moon from the 1960s with more recent LRO images to identify any changes on the lunar surface.

—Katherine Kornei (@KatherineKornei), Contributing Writer

This article is part of our ENGAGE collection, which provides science news for teachers to use in their lessons. Take a look at all the ENGAGE articles and let other educators know how you used this one in your activities by leaving a comment.

Reference: Kornei, K. (2023). A failed lunar mission is discovered by a current lunar mission. Eos, 104. https://doi.org/10.1029/2023EO230374. Published on October 3, 2023.

Text © 2023. The authors. CC BY-NC-ND 3.0

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