Virginia Tech Magazine
Spring 2009

Stepping stones to the moon--and beyond
Rendering of the Lunar Reconnaissance Orbiter

Rendering of the Lunar Reconnaissance Orbiter
"From our home on the Earth, we look out into the distances and strive to imagine the sort of world into which we were born.... Our immediate neighborhood we know rather intimately. But with increasing distance our knowledge fades, and fades rapidly, until at the last dim horizon we search among ghostly errors of observations for landmarks that are scarcely more substantial. The search will continue."

Realm of the Nebulae

American astronomer Edwin Hubble wrote these words in 1936, and he has proven remarkably prescient, save for one point. Despite six lunar landings from 1969 to 1972, we know less about our immediate neighbor than we do about Mars.

Look for that to change this spring, however, when NASA launches the Lunar Reconnaissance Orbiter, the first phase of humankind's newest mission to the moon--and a project engineered, in part, by several Hokies.

A step back, a leap forward

Dubbed Time's third-most important invention of 2008, the orbiter, or LRO, is tasked with positioning humankind to return to the moon. Only slightly larger than an Austin Mini-Cooper, LRO will meet an incredible set of mission objectives, including measuring the moon's topography, lighting conditions, and natural resources, such as potential minerals to be mined. Data reported by the orbiter will be used to determine safe landing sites for larger spacecraft and locations for human-manned outposts and will tell researchers how radiation dangers can be minimized.

A perhaps inevitable question is why we should expend so much time and money to seemingly retrace our steps. Yet this is a pioneering mission in several ways, including its new approach to studying the moon.

The focus of the original lunar exploration missions was to touch down on the moon and then return safely, explains David Everett (electrical engineering '86), technical lead for the project. To do so, the spacecraft took what Everett calls "the lowest energy route," which was to approach via the moon's equator. "The problem with the lunar equator is that the environment is nasty," Everett says. "The sun shines for 14 days, and the high temperatures approach 250 degrees Fahrenheit. Then it is dark for 14 days, and the temperature goes down to -220 degrees F."

This lunar mission will instead focus on gathering information during a year-long polar orbit. "At the poles, the sun always comes in at a low angle," Everett says. "There are mountains that are always in the sunlight where we can continuously generate solar power, and there are craters that are permanently shadowed, possibly containing frozen water. LRO is providing the data needed to generate maps for future explorers and to find the landing sites and the resources that those explorers will need." 

Exploring new frontiers

for lunar exploration

To find landing sites, generate maps, and provide critical data that will answer hundreds of questions about the moon, the orbiter will carry seven instruments:

* Cosmic Ray Telescope for the Effects of Radiation will determine the moon's radiation environment, providing data for the potential impact of exposure to human and other life, and will test how a type of plastic that is like human tissue reacts to and absorbs that radiation.

* Diviner Lunar Radiometer Experiment will measure surface and subsurface temperatures and identify potential ice deposits, rough terrain, and other landing hazards.

* Lyman-Alpha Mapping Project will use the ultraviolet spectrum to map the entire lunar surface, search for surface ice and frost in the polar regions, and provide images of permanently shadowed regions illuminated only by starlight.

* Lunar Exploration Neutron Detector will create high-resolution maps of hydrogen distribution and gather information about the neutron component of lunar radiation. An absence of neutrons will indicate concentrations of hydrogen and, potentially, frozen water.

* Lunar Orbiter Laser Altimeter will measure landing site slopes and lunar surface roughness, generate high-resolution three-dimensional maps of the moon, and measure lunar topography.

* Lunar Reconnaissance Orbiter Camera will capture high-resolution black-and-white images of the lunar surface, including images of the lunar poles down to 1 meter, and will image the lunar surface in color and ultraviolet to provide data on polar illumination conditions, potential resources and hazards, and options for safe landing sites.

* The Mini-RF Technology Demonstration will search for subsurface ice deposits and take high-resolution imagery of permanently shadowed areas of the lunar surface.

The sophistication and scope of the instruments [see table at right] that will convey mass amounts of data is particularly impressive given that the project itself was initially conceived in 2004 and that the preliminary design was only reviewed three years ago, Everett says. "This is an incredibly fast development for such a complicated system operating in a very visible role, and it would not have been possible without this team."

The team of more than 1,100 people includes Hokies from several agencies playing key roles [see sidebar on page 18]. These alumni contributed directly to designing, building, testing, and supporting LRO's systems--especially when it came to anticipating potential problems that could throw off the entire mission.

Indeed, the very nature of the polar orbit has required new ways of thinking about numerous aspects of the mission. For example, when John Lyons (physics '79) was planning and testing LRO's solar arrays, which will supply power to the orbiter by converting sunlight to electricity, he had to consider the extreme conditions that the orbiter will face.

"This solar array design was particularly challenging because the array has to survive thousands of very rapid temperature swings," Lyons explains. "In the very low lunar orbit, the temperature can go from as cold as –275 degrees F to as hot as 275 degrees F in a matter of minutes as LRO emerges from the moon's shadow, and the orbiter will cool off just as rapidly as it re-enters the shadow."

The drastic degree changes are also a potential concern for the output of the Optical Bench Assembly, which houses three instruments that will view the moon's surface and gather data to map it, and the Star Tracker Assembly, which is part of the Guidance Navigation Control System. As these structures continue to warm and cool rapidly and drastically during orbit, their expansion and contraction could cause instruments to focus on the wrong point and gather data that would be erroneously attributed to the intended coordinates, says Bill Chang (civil engineering '77; M.S. mechanical engineering '82). And although the amount of expansion and contraction would be extremely small, Chang points out that even the slightest error would make a huge difference.

"Consider that LRO's orbit altitude is 30 to 70 kilometers above the moon's surface," he says. "At a nominal altitude of 50 kilometers, if the instruments are off point by 1 arcsec, or 1/360th of a degree, that's approximately 8 feet. So if we have a pointing error of 5 arcsec, we will miss the target by some 40 feet." Accuracy is vital here because of the mission objective to find suitable landing sites, he adds. "We cannot afford to pick landing sites that we believe to be flat and clear of debris but are actually dotted with boulders or rock formations, all because our measurements were off." Chang led the design of a thermal control system that will combat this problem by maintaining a reasonably consistent temperature for the two assemblies regardless of where the LRO is in orbit.

The need to monitor the orbiter's progress led scientists to create a system that will use--much like something out of an Austin Powers film--an Earth-based laser. Team lead Ron Zellar (physics '91) explains, "Laser light-pulses will be transmitted to a small, two-inch aperture telescope aboard the LRO when it is in orbit. The light is transferred to a detector that records the arrival time of the laser pulse." This information, he says, will help determine where the LRO is and will contribute to the generation of lunar maps and science data. The laser-ranging system is the first of its kind and will be the first to operate routinely past Earth's orbit.

Another departure for this lunar mission from the original forays to the moon is the partnership forged with scientists from the Russian Institute for Space Research, which developed the Lunar Exploration Neutron Detector. Lead Spacecraft System Engineer Michael Pryzby (mechanical engineering '89) traveled to Moscow several times and met scientists who had worked with Yuri Gagarin, the first human in space and the first to orbit the Earth. "It has been a thrill knowing the first time we went to the moon, it was as part of the space race against the Russians. Now, we get to go together."

Pryzby was fascinated by the differences in design and testing philosophies between Russian and American engineers. "I have the utmost respect for their team," he says. "Each person is talented and extremely knowledgeable--and the kicker is, they do all this in two languages."

Testing... 3... 2... 1...

Because LRO will rely on innovative and complex systems to accurately report vast amounts of data, testing the new technologies has been vital. Take the experience of Jeff Hampton (mechanical engineering '78; M.S. '82), who helped with the vibration testing of the orbiter, during which LRO was placed on a large table that shakes violently, simulating the conditions of liftoff aboard an Atlas rocket.

"As a mechanical engineer, this is good as it gets," Hampton says. "Having the responsibility of shaking a $175 million piece of equipment hard enough to properly test it but not so hard as to damage it can get very exciting, to say the least."

A graphic of the lunar orbit insertion sequence, which could take two to four days to complete.
A graphic of the lunar orbit insertion sequence, which could take two to four days to complete.
One cause for excitement, as Hampton calls it, arose when the engineers were planning the test. "I discovered that due to an unusually large offset of the spacecraft center of gravity, not only did we have the normal concerns about not damaging the spacecraft during testing, we also had a risk of destroying the tester itself. This was truly a unique situation."

This challenge was but one example of the LRO team trying to predict and prepare for every possible outcome. "We have tested everything we can test," Everett says. Yet there remains a huge amount of pressure on everyone who has been involved with the mission. "In no other business does the first unit need to work perfectly," he adds. "This is a very unforgiving business."

Or, as LRO Flight Software Lead Mike Blau (electrical engineering '85) points out, "Everything has to go right, or we'll fly right past the moon."

The ultimate test, of course, will come once the orbiter is launched.

"For the launch, we will strap our 2-ton spacecraft on top of a Atlas V 41 rocket containing a million pounds of rocket fuel," Everett says. "The rocket will burn that fuel in three burns in 19 minutes, leaving LRO traveling at more than 24,000 miles per hour." When LRO reaches the moon after approximately four days, it will then enter an elliptical orbit, or commissioning orbit, from which it will move into its final orbit, a circular polar orbit at a little more than 30 miles above the lunar surface.

And that's when the real mission will begin.

Several Hokies from numerous organizations have been----and will continue to be----key players in the Lunar Reconnaissance Orbiter mission.

Kneeling, front row (from left to right): Caitlin Eubank '04, Michael Pryzby '89, Rivers Lamb '00, Ron Zellar '91; standing, back row: Jason Badgley '01, Tim Schwartz '08, Bill Chang '77, Craig Stevens '00, David Everett '86, Greg Greer '86, Sharon Peabody '96, Mike Blau '85, Jeff Hampton '78, Brad Kercheval '91.

Several Hokies from numerous organizations have been--and will continue to be--key players in the Lunar Reconnaissance Orbiter mission. Here are the ones of whom we're aware to date:

Jason K. Badgley (electrical engineering '01), propulsion and deployment electronics lead engineer, NASA (Goddard Space Flight Center)

Mike Blau (electrical engineering '85), flight software lead engineer, NASA (Goddard Space Flight Center)

Bill Chang (civil engineering '77; M.S. mechanical engineering '82), thermal engineer, Edge Space Systems

Shelly (Bright) Conkey (aerospace engineering '97), mechanical analyst for deployable systems, ATK Space Systems

Caitlin Eubank (aerospace engineering '04), propulsion engineer, NASA (Goddard Space Flight Center)

David Everett (electrical engineering '86), mission systems engineer, NASA (Goddard Space Flight Center)

Greg Greer (political science '86), ITOS product lead, The Hammers Company

Jeff Hampton (mechanical engineering '78; M.S. '82), mechanical engineer, ATK Space Systems

Michael Hersch (M.S. mechanical engineering '86), mechanical systems lead for solar array system, ATK Space Systems

Bradford P. Kercheval (electrical engineering '91), power system electronics engineer, MEI

Rivers Lamb (aerospace engineering '00; M.S. '02), flight dynamics ground systems lead engineer, NASA (Goddard Space Flight Center)

John W. Lyons (physics '79), solar array lead, NASA (Goddard Space Flight Center)

Sharon Peabody (engineering science and mechanics '96; M.S. mechanical engineering '97), thermal engineer, Edge Space Systems

Michael Pryzby (mechanical engineering '89), spacecraft systems engineer, ATK Space Systems

Timothy Schwartz (M.E. mechanical engineering '08), structural dynamics test engineering, NASA (Goddard Space Flight Center)

Craig L. Stevens (aerospace engineering '00; M.S. '02), mechanical analysis lead engineer, NASA (Goddard Space Flight Center)

Ron Zellar (physics '91), laser ranging lead engineer, NASA (Goddard Space Flight Center)

A broader landscape

Aside from the vast quantities of data that the orbiter will gather, there are other justifications for again venturing forth to the moon.

"I agree with Stephen Hawking when he says that the long-term survival of our species depends on expanding our habitat beyond the Earth," says Blau. "With only one planet, we are too vulnerable to a single catastrophe. LRO is the first step toward creating permanent lunar and Martian outposts, and those outposts are the first step toward sustainable human habitation."

Pryzby agrees. "We often debate if money spent in the space program is money well spent. What I have come to peace with is that this is a small investment in the future. The Earth has limited resources. If we are to survive as a species, we will need to leave this planet. To do that, we will need to learn to survive while off this planet. The moon offers the best place to practice."

This same belief is the foundation of NASA's Exploration Initiative: to develop humankind's ability to go beyond low-Earth orbit and explore the solar system firsthand, not simply via computers and unmanned spacecraft. "Before we can go to Mars or an asteroid, we will try out our camping gear in the backyard," Everett notes. "We will learn how to live for long periods of time on another body, with limited resources, outside the benign environment of the Earth."

Sharon Peabody (engineering science and mechanics '96; M.S. mechanical engineering '97), who aided in the design and analysis of the orbiter's thermal control system, says that a human outpost on the moon "could serve as a mid-port for the building and launch of spacecraft and people. It would be cheaper and easier to launch a spacecraft into a moon-bound orbit, where it could then stock up on fuel, personnel, and hardware before launching into deeper space." Such comments elicit the visions of lunar settlements that sci-fi movies have been showing us for decades, images that call to mind the explorers whom Edwin Hubble foresaw.

Looking at the mission from a philosophical perspective, Chang posits, "Two questions that scientists have been striving to answer are ‘What happened at the beginning, and how was the universe formed?' and ‘Are we alone in the universe?'" A lunar presence, he says, will allow scientists to explore the Big Bang Theory. "The thinking is that the further into space--closer to the epicenter of the explosion--we can see, the more insight we will gain about what actually happened." Permanent, larger, and more advanced telescopes placed on the moon will be better able to provide that view; telescopes based on Earth reflect atmospheric distortion, and those currently in orbit, such as the Hubble Space Telescope, are difficult to update and repair.

"A base on the moon will also allow us to establish a new jumping-off point for human exploration of neighboring planets and, eventually, the universe," Chang adds. "These things will not happen in our lifetime, but every journey starts with the first step."

That first step will come when the orbiter is launched late this spring. Not only will LRO carry the hopes and dreams of the men and women who worked on it, but it also will fulfill what Hubble considered the human need to search for new frontiers. "The urge is older than history," he concluded. "It is not satisfied, and it will not be suppressed."

For more on the mission and for specific launch information, go to

HOKIE VOICES: Alumni share their thoughts on their roles in NASA's LRO project

Reacting to the LRO's being named third-most important invention of 2008:

Jason Badgley (electrical engineering '01): I felt honored. Because of all the politics involved with working for NASA, our missions can sometimes be daunting tasks. But to see the general public provide such support for this mission gives me a sense of pride.

Mike Blau (electrical engineering '85): It is always nice to be recognized publicly for your work. Of course, we still have to launch LRO and get it to the moon. Maybe then it will really be worthy of a prize. I didn't mind losing to the Tesla roadster, either. I wish I could afford one of those.

Shelly (Bright) Conkey (aerospace engineering '97): It feels pretty impressive to have contributed to something that gets that kind of national press.

Caitlin Eubank (aerospace engineering '04): What were you thinking?! No, just kidding. I was thinking, "Wow! And I got to have a part in that!"

David Everett (electrical engineering '86): I have been working for NASA for 17 years, but never before on anything that has received so much attention. To be recognized as Time's No. 3 invention of 2008 is very exciting. I sent the article to all of my relatives. But it also reminded me that there are many people watching what we do. It is critical that we do whatever we can to make sure this system has the best possible chance of being successful through the rigors of launch and operation in the vacuum and radiation environment of lunar orbit. So, I guess I would have to say that the Time article made me a bit nervous, but it is the good kind of nervous that makes you really concentrate on success.

John Lyons (physics '79): Excited. And then I thought, "Why only third?"

Mike Pryzby (mechanical engineering '89): My first reaction was that we designed LRO two years ago, so maybe they were a little late recognizing us. Then I thought, I guess we should prove it works first, so maybe they are a year early. It will be nice having this thing operational and sending back data. I guess at that point, we all will be breathing a little easier. But to be recognized at all is a nice honor. To do what we have in the time we were given is a big accomplishment. There were a lot of critics out there who said we could not do this in the time we were given. It has been a credit to this team that they have proven the critics wrong so far. That first picture the Orbiter returns will mean a lot to us.

Ron Zellar (physics '91): I was a bit surprised. To me, I had been helping to build another space satellite, albeit, a really cool one. But to have LRO named as one of the most important inventions of 2008? Well, I still don't believe it. It's really great to be part of a mission that has captured this much public attention.

Their advice for fellow alumni and/or students:

Bill Chang (civil engineering '77; M.S. mechanical engineering '82): There are endless numbers of new discoveries to be made in space. Most will be remarkable, some may even scare us but all will be enlightening. Shows like Star Trek are today's science fiction but may become tomorrow's reality. President Kennedy's directive for NASA to put a man on the Moon within a decade seemed far fetched in the 60's but it, too, became reality. The future is a blank slate—the only question we need to ask ourselves is how we will shape it. Engineers being trained today will have the daunting task of helping to write that future. Space exploration was, is, and will always be exciting! So I say to my fellow Hokies, "Thrill me!"

Eubank: One, make sure you eat at the Homeplace at least once. Two, Gillie's has the BEST breakfast. Three, enjoy Blacksburg. It may seem small, but you'll miss it when you leave! Four, get your hands on everything. Try to do as much in the labs as you can; that experience can really be invaluable.

Everett: Designing and building spacecraft is difficult, and that is why I love my job. The challenge of really tough mental problems, combined with the camaraderie of a common cause, makes my job fun. My advice to students is find your passion, find a job that will keep you thinking and occasionally keep you up at night. Find something you can pour your energy into and have it come back to you doubled. Don't take the easy road--it will lead you to boredom in the long run. The best example I can give to the current generation is video games--initially, level one might be interesting, but it quickly becomes a chore to play it over and over because it becomes too easy. The best games get harder and harder as your skill improves. You need to choose a path in life that will do the same.

Jeff Hampton (mechanical engineering '78; M.S. '82): We at ATK (formerly Swales Aerospace) have hired many graduates of Virginia Tech (I was actually the first they hired in 1982). These hires have consistently been some of our stronger employees. Wherever your students wind up working, I cannot overemphasize the importance of developing good team-working skills. The ability to not only make suggestions, but to also be open to other ideas and to rely on team members for their support is indispensable. The most successful and enjoyable programs that I have been involved in encouraged and accepted input equally from all team members.

Rivers Lamb (aerospace engineering '00; M.S. '02): Space missions require a wide variety of people from a wide variety of disciplines. Folks from almost any major at VT can play a role at NASA, from engineering and science to public affairs, business, and political science.

Lyons: Go, Hokies!

Pryzby: VT, Maryland, and Penn State all have a large contingent of graduates in this area. There has always been a friendly rivalry amongst us. While we focus a bit on sports, we do keep it good natured. However, after April 16th, things changed a bit for us. A lot of us on the project got together and talked a little bit more. We relived our experiences at Tech and felt a little more connected. We were all impressed with the Hokie community and their strength. For me on that day, e-mails were flying from my old fraternity (TKE). All the alumni were getting everyone there to check in, brothers and little sisters. We were concerned and wanted to make sure everyone was safe. We just wanted to help in some way. It was very difficult for many people that day. Our hearts go out to all the families that were affected. The concern and caring for everyone there and everything that happened was inspiring, though. Since then, my sense of pride in the Hokie community has increased. I have gotten in touch with more of my friends from Tech since then. We have all re-connected and come closer together. I am really honored to be associated with the university in the way it handled itself since the tragedy. I was impressed with all the students who returned and the way they have presented themselves. I hope this mission will be successful and maybe bring a little bit of honor and pride to Hokie Nation. I am extremely proud of how far the university has come since my time there.

Craig Stevens (aerospace engineering '00; M.S. '02), mechanical analysis lead engineer: As an undergraduate aerospace engineering student, I participated in a design-build-fly satellite project named "Hokiesat." Working with the seniors and aerospace professionals gave me excellent insight into the aerospace field. After receiving my BS, I attended graduate school where I continued my work on Hokiesat. My thesis focused on the design, fabrication, and testing of the Hokiesat structure. The entire experience prepared me for my role at NASA and on LRO. Hokiesat gave students like me the opportunity to prepare ourselves for a career in the aerospace industry. It provided real-world experience and was a valuable networking tool. I highly recommend participating in student projects during your time as a student and alumnus or alumna.

Zellar: One's career and life don't always take a straight path. Never stop learning. You never know when you'll need the knowledge.

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