A team at NASA’s Langley Research Center in Hampton, Virginia, has captured first-of-its-kind imagery of a lunar lander’s engine plumes interacting with the Moon’s surface, a key piece of data as trips to the Moon increase in the coming years under the agency’s Artemis campaign.
The Stereo Cameras for Lunar-Plume Surface Studies (SCALPSS) 1.1 instrument took the images during the descent and successful soft landing of Firefly Aerospace’s Blue Ghost lunar lander on the Moon’s Mare Crisium region on March 2, as part of NASA’s Commercial Lunar Payload Services (CLPS) initiative.
The compressed, resolution-limited video features a preliminary sequence that NASA researchers stitched together from SCALPSS 1.1’s four short-focal-length cameras, which were capturing photos at 8 frames per second during the descent and landing.
The sequence, using approximate altitude data, begins roughly 91 feet (28 meters) above the surface. The descent images show evidence that the onset of the interaction between Blue Ghost’s reaction control thruster plumes and the surface begins at roughly 49 feet (15 meters). As the descent continues, the interaction becomes increasingly complex, with the plumes vigorously kicking up the lunar dust, soil and rocks — collectively known as regolith. After touchdown, the thrusters shut off and the dust settles. The lander levels a bit and the lunar terrain beneath and immediately around it becomes visible.
Rob Maddock
SCALPSS project manager
“Although the data is still preliminary, the 3000-plus images we captured appear to contain exactly the type of information we were hoping for in order to better understand plume-surface interaction and learn how to accurately model the phenomenon based on the number, size, thrust and configuration of the engines,” said Rob Maddock, SCALPSS project manager. “The data is vital to reducing risk in the design and operation of future lunar landers as well as surface infrastructure that may be in the vicinity. We have an absolutely amazing team of scientists and engineers, and I couldn’t be prouder of each and every one of them.”
As trips to the Moon increase and the number of payloads touching down in proximity to one another grows, scientists and engineers need to accurately predict the effects of landings. Data from SCALPSS will better inform future robotic and crewed Moon landings.
The SCALPSS 1.1 technology includes six cameras in all, four short focal length and two long focal length. The long-focal-length cameras allowed the instrument to begin taking images at a higher altitude, prior to the onset of the plume-surface interaction, to provide a more accurate before-and-after comparison of the surface. Using a technique called stereo photogrammetry, the team will later combine the overlapping images – one set from the long-focal-length cameras, another from the short focal length – to create 3D digital elevation maps of the surface.
The instrument is still operating on the Moon and as the light and shadows move during the long lunar day, it will see more surface details under and immediately around the lander. The team also hopes to capture images during the transition to lunar night to observe how the dust responds to the change.
“The successful SCALPSS operation is a key step in gathering fundamental knowledge about landing and operating on the Moon, and this technology is already providing data that could inform future missions,” said Michelle Munk, SCALPSS principal investigator.
Michelle Munk
SCALPSS principal investigator
It will take the team several months to fully process the data from the Blue Ghost landing. They plan to issue raw images from SCALPSS 1.1 publicly through NASA’s Planetary Data System within six months.
The team is already preparing for its next flight on Blue Origin’s Blue Moon lander, scheduled to launch later this year. The next version of SCALPSS is undergoing thermal vacuum testing at NASA Langley ahead of a late-March delivery to Blue Origin.
The SCALPSS 1.1 project is funded by the Space Technology Mission Directorate’s Game Changing Development program.
NASA is working with several American companies to deliver science and technology to the lunar surface under the CLPS initiative. Through this opportunity, various companies from a select group of vendors bid on delivering payloads for NASA including everything from payload integration and operations, to launching from Earth and landing on the surface of the Moon.
