In 1986, as a Green Mountain High School senior in Lakewood, Colorado, Daniel Kubitschek watched the spacecraft Voyager's encounter with Uranus on NASA TV and decided he wanted to work at the Jet Propulsion Laboratory one day.
One of four brothers to earn CU-Boulder engineering degrees, Kubitschek navigated his way through a bachelor's degree (MechEngr '90), a stint at the Applied Physics Laboratory in Maryland, and two graduate degrees (MS AeroEngr '94, PhD '97) before landing at JPL in the fall of 2000.
"I almost couldn't believe it when they made me an offer. I actually got an offer from the optical navigation group, and that's not the reason why I originally went to interview," recalls Kubitschek. "I was hired on to work the Deep Impact mission. They made me the offer and said this will be your focus for the next five or six years. It was just a fortunate opportunity."
One of NASA's most popular and successful unmanned missions in history, Deep Impact's goal—to remotely fly a spacecraft into the nucleus of Comet Tempel 1 while a second spacecraft observed the impact—drew interest from around the world. The first spacecraft, called an impactor, was designed to target, impact, and excavate the debris flying from the comet's nucleus. The other, called a flyby, was to take both optical and infrared measurements after impact, providing the scientific community with new insights into comets, which many researchers believe played a central role in the birth of the solar system, and perhaps even the birth of life.
Approximately two years after Kubitschek was hired, he became the lead system engineer in charge of the autonomous navigation system ("autonav") responsible for tracking, targeting, and impacting the comet. He would go on to serve as flight director for the impactor spacecraft during the encounter on July 4, 2005.
"Initially, I started out in algorithm development and was also involved with preliminary analysis and testing of the autonomous navigation system," he says. "We actually flew two systems, one on the impactor spacecraft to target and intercept the nucleus, and one on the flyby spacecraft to track the nucleus during the flyby encounter. My work evolved into being the autonav team lead during the last three years of development and the six-month cruise, and then focusing on the impactor encounter as the impactor sequence design lead and flight director."
The two spacecraft launched as a unit in January 2005, and after a six-month voyage, separated 24 hours before estimated impact.
"The thing about the autonav system, unlike most of the rest of the systems, is that we designed it specifically for the encounter phase, which was basically the last day and a half of the mission," says Kubitschek. "So our role as the autonav team during cruise was to support activities, to be involved in calibrating the optical instruments, to run encounter rehearsals on the ground and on the spacecraft, and really to focus on making sure everything was in order and we were fully prepared for the encounter event."
On July 4, the impactor collided with Tempel 1, with the autonav system performing three autonomous targeting maneuvers during the last two hours of flight. The flyby spacecraft observed the resulting ejected matter and took measurements before it assumed a shield attitude for passage through the comet's inner coma—the cloud of gas and dust surrounding its nucleus.
"Our last maneuver on the impactor spacecraft was 12 and one-half minutes out, and after we performed that maneuver we were going in, and the attitude control system was keeping the imager straight down the velocity vector looking at the impact site for as long as possible, until dust impacts upset the spacecraft. As the images were telemetered to the ground in real-time, we could see the incredible details on the surface and knew that we were on a collision course and would only have to wait for flyby images to confirm impact," says Kubitschek.
"The last impactor image was taken about four seconds before impact and yielded the highest resolution images ever taken of the surface of a comet nucleus. On the flyby spacecraft it was essentially the same thing, but without autonomous maneuvers. We began processing images two hours before the expected time of impact and we tracked the nucleus and impact site until shield attitude," he says. "Once the images of the impact flash were received on the ground, we knew we had been successful and the entire control room erupted in cheers and congratulations. The objective of the mission was really to understand the internal composition of the nucleus. We were amazed by the images that were taken, and there have been a number of articles published in Science magazine on the results."
In recognition of his role in Deep Impact's tremendous success, Kubitschek was awarded the Institute of Navigation's 2005 Tycho Brahe Award, joining an exclusive list that includes University of Texas at Austin Associate Professor E. Glenn Lightsey, Texas A&M University Distinguished Professor John L. Junkins, CU-Boulder Professor Penina Axelrad, NASA and APL flight director Robert W. Farquhar, and honorary AIAA fellow and National Academy of Engineering member Richard H. Battin. Kubitschek also was awarded the NASA Exceptional Achievement Medal in spring 2006.
"If it wasn't for the influence of people like Malcolm Schuster at APL, George Rosborough and George Born in the (CU-Boulder) aerospace department, and Patrick Wiedman in the (CU-Boulder) mechanical engineering department, I wouldn't be here," Kubitschek says. "It feels like the opportunity of a lifetime, and I feel very fortunate to have been involved and particularly to be working at JPL."
These days Kubitschek remains with JPL, working as a resident engineer at Ball Aerospace & Technologies Corp. for NASA's Kepler Mission, the first mission capable of finding Earth-size planets orbiting other stars.
"It's a four-year mission," he says. "It's going to observe hundreds of thousands of stars simultaneously, basically stare at them for the better part of four years, and detect what's called a transit, or a change in brightness, due to Earth-like planets orbiting those stars in what's called a habitable zone: a range from the star that would perhaps allow water to exist in liquid form."
Ten or 15 years down the road, Kubitschek says he ultimately would like to take his experience to the academic world to teach and do research.
"I would love to end up at a university," he says. "I think I have an opportunity to gain an incredible amount of unique experience that I hope to one day pass on to students."