Leonard David's INSIDE OUTER SPACE

Astrobotic is developing navigation technologies to allow free-flying spacecraft to explore subterranean environments on the Moon, such as lava tubes.
Credit: Astrobotic Technology/RIS4E/SSERVI/Stony Brook University

Skylights on the Moon are collapses that occur over subsurface voids. Skylights occur in many terrestrial lava tubes, providing access, although sometimes requiring shimming down a rope. Shown here is a skylight in the Moon’s Marius Hills.
Credit: NASA/GSFC/Arizona State University

By tapping robotic and sensor technologies, a small free-flying spacecraft is being demonstrated to autonomously investigate lava tubes on the Moon.

Astrobotic Technology of Pittsburgh, Pennsylvania is partnering with scientists from the RIS4E node of NASA’s Solar System Exploration Research Virtual Institute (SSERVI), led by Stony Brook University.

High-priority targets

Lunar lava tubes are high-priority targets for scientific research because they provide access to geologic formations that have been shielded from space weathering for billions of years.

These features may contain a preserved record of the conditions present during the formation of the lunar mare.

While these tubes are rich in scientific samples, an Astrobotic statement explains that they could also be ideal locations for future human settlements because they provide natural protection from radiation and micrometeoroids.

The city of Philadelphia is shown inside a theoretical lunar lava tube. A Purdue University team of researchers explored whether lava tubes more than one kilometer wide could remain structurally stable on the Moon.
Credit: Purdue University/courtesy of David Blair

Lunar skylights

“While lava tubes are difficult to access because they are buried below the lunar surface, roof collapses, known as skylights, offer a tantalizing way to access the subsurface,” the Astrobotic statements adds. “Long hypothesized to exist, only in the past decade have numerous lunar skylights been detected from orbital imagery, and scientists have recently discovered that the Moon may host massive networks of lava tubes.”

Astrobotic field-tested their autonomous navigation in Aden Crater in the Potrillo Lava Fields, New Mexico. The geologic features in the field are an analog environment for the Moon or Mars. The team deployed with the SSERVI RIS4E team in March 2018. Credit: Astrobotic Technology/RIS4E/SSERVI/Stony Brook University

Sensing modalities

Under a research contract with NASA, Astrobotic has developed a custom navigation software product, known as AstroNav.

To explore sub-surface environments on the Moon, Astrobotic’s AstroNav employs both stereo vision- and LiDAR-based navigation, works without GPS or previously stored maps (neither of which exist in the target environment), and can operate in real-time.

Combining sensing modalities allows a spacecraft to perform a seamless traverse over the lunar surface before dropping into a skylight from above.

The Potrillo Lava Fields in New Mexico contain features that are thought to be analogous to the lava flows Moon and Mars, including skylights that could offer access to subsurface lava tubes.
Credit: Astrobotic Technology/RIS4E/SSERVI/Stony Brook University

Field testing

This past April, Astrobotic’s Future Missions and Technology team joined the RIS4E SSERVI team at a field test site in New Mexico to demonstrate a number of key technologies required for these Moon missions.

The field site — known as the Potrillo Volcanic Field — has volcanic features analogous to those found on the Moon and Mars, and the collaboration between the teams sought to address the challenges of conducting extra-planetary geologic data and sample collection from autonomous aerial science platforms.

RIS4E team members deploy a portable hyperspectral infrared camera to investigate the mineralogy of volcanic rocks at Kilbourne Hole in the Potrillo Lava Fields.
Credit: Astrobotic Technology/RIS4E/SSERVI/Stony Brook University

Astrobotic’s research was funded in part by NASA’s Small Business Technology Transfer (STTR) program. Under this contract, Astrobotic will perform a field demonstration of AstroNav technology in lava tubes in the coming months.

Go to this video showing RIS4E team members deploying a portable hyperspectral infrared camera to investigate the mineralogy of volcanic rocks at Kilbourne Hole in the Potrillo Lava Fields, available at:

https://www.youtube.com/watch?v=wZfidjKQrko&feature=youtu.be