Ground Control to Professor Thom: Inside Orlando’s Interstellar Inquiries

Thomas Orlando is a professor in the School of Chemistry and Biochemistry and co-founder and former director of the Georgia Tech Center for Space Technology and Research (CSTAR).

And over the past couple of months, he’s been quite busy. 

In a story widely carried by major media outlets, last month NASA announced that a study published in the journal Nature Astronomy shows evidence of water on the sunlit portions of the moon, through an effort involving the use of the NASA SOFIA flying observatory. Orlando is one of the study’s co-authors — he’s been working on the lunar water issue for many years and some of his research group’s modeling was critical to the paper.  

Orlando is also principal investigator for the Radiation Effects on Volatiles and Exploration of Asteroids and Lunar Surfaces (REVEALS) team based at Georgia Tech, part of a NASA project which is researching not only water on the moon, but also how to better protect astronauts from the dangers of space exploration. Orlando collaborates with University of Notre Dame colleagues on this project, and last month he learned he would be featured in a short “infomercial” about the research, which ran during halftime of the NBC national telecast of the Nov. 7^th Notre Dame-Clemson game. 

He’s also the recent winner of a major award from the American Vacuum Society (the national surface science society) for his work on integrating surface chemistry and physics into planetary science. The award is named for an un-official mentor who Orlando collaborated with in the early 1990’s. Add to that the renewal of Department of Energy funding for his research looking into minimizing the dangers of nuclear waste storage, and other NASA projects on future astronaut habitats, and you’ve got the makings of a busy 2021 for Orlando.

Add to that the renewal of Department of Energy (DOE) funding for his research looking into minimizing the dangers of nuclear waste storage, and other NASA projects on future astronaut habitats, and you’ve got the makings of a busy 2021 for Orlando.

Other than finding molecular water on the Moon, all of these projects gravitate towards Orlando’s fascination with radiation: either protecting astronauts from it in space, or finding new ways to deal with nuclear waste radiation on Earth. 

“My emphasis has always been on understanding radiation, how it affects surfaces and interfaces,” Orlando says. “For decades now, we have been moving these tools we’re using in different scientific communities to try and unravel what happens when you’re in a star-forming region, or on the Moon, and being irradiated by solar wind, or anywhere where you’re not protected from radiation.

“A big part of my portfolio is a strange mixture of atomic and molecular physics mixed in with surface physics and chemistry,” he says. “In fact, the program at DOE is all of these. The safe storage of nuclear waste, which is a very important environmental and potential national security issue, is essentially a very complicated solid-liquid interface problem that gets worse when you add radiation.”

An award honoring a mentor, research partner

Orlando, who has an adjunct appointment with the School of Physics, is the winner of the 2021 Theodore E. Madey Award, presented by the American Vacuum Society (AVS) and the Polish Vacuum Society. Madey, a physicist and longtime professor at Rutgers University, was a pioneer in expanding physics and chemistry to include the study of surfaces. 

According to the AVS website, the Madey Award is presented to scientists showing “outstanding theoretical and/or experimental research in areas of interest to the AVS and PVS, including surface science.” In Orlando’s case, the Madey Award is primarily for integrating surface physics and chemistry with planetary sciences – the kind of research Orlando is conducting with REVEALS.

Orlando will travel to Poland for a series of lectures in the summer of 2022; typically the Madey Award winner would make those appearances in 2021, but Orlando says the pandemic has forced changes to the schedule.

For Orlando, the Madey award represents a truly unique honor; it’s named for someone Orlando knew and worked with, a former colleague he called “a gifted and kind person.” They met when Orlando was a postdoctoral fellow at Sandia National Laboratory in New Mexico. Soon after they would begin research together, with Orlando helping Ted Madey organize conferences such as the Desorption Induced by Electronic Transitions (DIET) conference held in Callaway Gardens, Georgia, in April 2009 — an event that ultimately occurred some months after Madey’s death in summer 2008.  

“We were doing work on inelastic electron scattering, and I’ve never stopped doing it since then,” Orlando says. “But what I’ve done is move the tools necessary to study this, and that problem (electron-bombarded surfaces and interfaces) to the planetary sciences community. Ted did sort of the same thing, but towards the latter part of his career. He was very interested in planetary science. He, I, and a few others were sort of moving this area of surface science forward by directly linking it to problems in space science.”

REVEALS gets the NBC spotlight

Orlando has recently made significant progress in moving that combination of surface physics, chemistry, and planetary sciences: He currently leads the REVEALS team of scientists from Georgia Tech and other higher education institutions in its mission of finding potential resources such as water on the Moon. His team is also researching new materials and technologies to protect future astronauts from radiation bombardment as they explore the Moon, Mars, or near-Earth asteroids. 

One of those partner institutions is Notre Dame, which helped create a recent NBC video that aired during its nationally-telecast November 7^th football game with Clemson.

Notre Dame professor Jay LaVerne is a good friend of Orlando’s, which is how LaVerne ended up as a part of the original REVEALS team. “He’s the first guy I thought of when I wanted to simulate cosmic rays and the proton bombardment coming from solar winds,” Orlando says. “We can simulate the low energy part of this, but he can simulate the high energy part better. Together we can do a very good and comprehensive study.”

NBC is focusing mostly on the Notre Dame Radiation Laboratory, but did bring a crew to Georgia Tech’s Marcus Nanotechnology Building to shoot an interview with Orlando. The NBC crew observed all campus virus protection protocols during videotaping, so it did not shoot in Orlando’s REVEALS lab, which is in tighter quarters. Instead, he’s given time to speak in the video about the project’s mission.

“Developing a spacesuit is a multi-decade process, and it’s really complicated,” he says. “If it doesn’t stand up to radiation, it’s pretty useless. We’re looking at using nanocomposite materials, which offer stronger protection, but also lighter weights and more flexibility. The suits that we want to make will be good for protecting them from radiation, but also protecting them from dust. That’s also a serious problem when astronauts go exploring. The philosophy is risk mitigation,” he adds. The suit work is carried out in collaboration with other GT-REVEALS researchers in the School of Chemistry and Biochemistry, School of Materials Science and Engineering, and School of Physics and is indeed a multidisciplinary effort.

Orlando shares that, eventually, he and the REVALS team hope to develop and use materials that will turn the entire spacesuit into a radiation detector.  

Water, water everywhere – even on the moon

The recent discovery of molecular water on the moon also ties into REVEALS. The “V” in REVEALS refers to volatiles — molecules like hydrogen or water that are needed and can be produced by the bombardment of lunar regolith (the fine, fragmented soil that covers lunar bedrock) by solar wind or micrometeorites. REVEALS studies how this process could happen. If there are enough useful volatiles, could they somehow be ‘mined’ by astronauts to be used on site? This is critical for long term human exploration and presence on the moon, which is the goal of the NASA Artemis program.

Orlando explains that that’s why the October Nature Astronomy research paper is so important. “We’re very, very active in understanding how water is formed on the moon, how water moves on the moon, how water is lost from the moon, and how it’s kept on the moon,” he says. “The paper says water is kept in higher abundances than what most people think — and subsurface too. It (the research) does really contribute significantly to the overall possibility of extracting water and using it as a resource for a longer-term presence.”

The researchers discovered this by asking for observation time from SOFIA – the Stratospheric Observatory for Infrared Astronomy, that NASA flies on a modified Boeing 747 so it can observe space above the clouds.  

That fact, and SOFIA’s Faint Object Infrared Camera, were the primary factors in helping to find evidence of water on the moon, Orlando says. “When you’re above the cloud layer, you automatically subtract out your water background (from the clouds), so you could do a real mapping of what’s on the moon with the telescope without water interference. That’s number one, a background-free measurement.”

The second factor is the infrared camera’s ability to capture optics on a particular 6 micron-based spectrum that helped show evidence of actual molecular water, and not just its separate components of hydrogen and oxygen. As the Nature paper puts it, water has been detected before by other spacecraft, but “whether the hydration is molecular water (H₂O) or other hydroxyl (OH) compounds is unknown, and there are no established methods to distinguish the two using the 3 µm (microns) band of specialized telescopes and spectroscopes. However, a fundamental vibration of molecular water produces a spectral signature at 6 µm (microns) that is not shared by other hydroxyl compounds.” Using SOFIA, observations reveal “a 6 µm feature at high lunar latitudes, due to the presence of molecular water on the lunar surface.”

“It (SOFIA) was mostly used for astrophysics. We’d never pointed it at the moon before to look for water,” Orlando says. Co-author Paul Lucey and graduate student Casey Honniball (first author of the study) were awarded time on SOFIA. Orlando and Brant Jones, a Georgia Tech REVEALS co-investigator, did computer modeling to help explain the results and to determine how much water could be there — either on the soil grains, trapped between the grains, or in the grains themselves. Jones and Orlando are measuring this directly, now, in Orlando’s Electron and Photon Induced Chemistry on Surface (EPICLS) Lab.

Radiation waste on Earth, radioactive-free habitats in space

Orlando’s interest in radiation is also a part of a Department of Energy Office of Science contract that funds the Pacific Northwest National Laboratory Interfacial Dynamics in Radioactive Environments and Materials (IDREAM2) Energy Frontier Research Center (EFRC). IDREAM2 is looking into the fundamental physics and chemistry associated with the storage of nuclear wastes across the DOE complex. This includes relics of Cold War weapons production.

Orlando is the science lead on the radiation cross cutting theme in IDREAM2. “Safe storage, treatment and monitoring the radioactive waste legacy is an important problem set the DOE is dealing with,” he says. “We look very carefully at what happens at the interfaces. We (Georgia Tech) have been active in this for a very long time.” An important waste issue is the production of molecular hydrogen and the radiation induced damage of water and the waste forms. “It is actually the reverse of what we’re doing for NASA. It’s the splitting and breaking up of water and the buildup of hydrogen, and that needs to be understood and controlled.”

Orlando is hoping that his team’s studies will help scientists predict how nuclear waste will behave and ‘age’ so that governments can know how to best deal with the longer term storage and treatment options.

His interest in radiation also explains his involvement in another NASA program, HOME (Habitats Optimized for Missions of Exploration). This program involves interdisciplinary groups of scientists at seven universities, all with the goal of designing and manufacturing what NASA is calling “SmartHabs,” fully autonomous habitats that will “keep astronauts alive while they are resident, and keep the vehicle/habitat alive (operational) while they are not,” according to Georgia Tech’s HOME website.