Illustration of of Mars Odyssey
Mase talks about the complexities of spacecraft navigation.

Caught unawares, Odyssey lead navigator Bob Mase mumbled "what?" when Ed Weiler, associate administrator for NASA's Office of Space Science announced that Mase and the Odyssey navigation team had won one of Aviation Week and Space Technology magazine's annual Laurel awards. Mase and his fellow navigators have been so busy with Mars Odyssey mission activities that they have had little time to pay attention to anything else.

Odyssey entered orbit around Mars flawlessly during the evening of Oct. 23, 2001, at JPL. The next day an elated Mase reported the precision targeting at a press conference. He also noted that no further maneuvers would be necessary to adjust the orbit prior to aerobraking, a several-month process to shorten and circularize the orbit for science-gathering activities.

At the time of orbit insertion, Odyssey had traveled 457 million kilometers (284 million miles) and flew within 1 kilometer (0.6 miles) of its target. "That's the equivalent of making a touchdown pass from Los Angeles to New York," Mase said.

Aviation Week & Space Technology

The Mars Odyssey navigation team won a Laurel in the space category for Aviation Week & Space Technology magazine's 2001 awards. The team's accomplishment was noted in the magazine's Feb. 4 issue along with other winners.

In its announcement, Aviation Week noted "Bob Mase, lead navigator for NASA's Odyssey spacecraft project at the Jet Propulsion Laboratory, and the Odyssey navigation team, for scoring a bull's-eye last October by flying to within 1 km. of the orbit insertion aim point."

The team varied in numbers from one to fourteen from the development phase through aerobraking. In alphabetical order, members included: Peter Antreasian, Darren Baird, Julia Bell, Dan Burkhart, Eric Graat, Moriba Jah, David Jefferson, Brian Kennedy, Tomas Martin-Mur, Bob Mase, Tim McElrath, Brian Portock, Mark Ryne and John Smith.

Cover art courtesy of Aviation Week & Space Technology

Navigation is a 1-2-3 Approach

Mase has been on the navigation teams of several programs since joining the Jet Propulsion Laboratory in 1991, among them Mars Observer, Galileo and Mars Global Surveyor prior to Odyssey. He explains that there are three basic navigation disciplines: 1) trajectory design, 2) orbit determination, and 3) maneuver design.

"I like to think of them as answering three basic questions," Mase said. "One, where do we want the spacecraft to go? Two, where is it now? Three, how do we get from where we are now to where we want to be?" He says he has been lucky enough to experience them all.

Building a Career in Spacecraft Navigation

Mase's first JPL job was as an orbit determination analyst on Mars Observer, collecting tracking data to determine the spacecraft's exact location and destination. He then moved to Galileo in the same function for a year, and then three years as a maneuver analyst, planning propulsive maneuvers to keep the spacecraft on the correct flight path.

Mase said, "I'm glad I was able to work on the Galileo program early in my career. It was a great learning opportunity during the long cruise to Jupiter."

By the time Mase joined the Mars Global Surveyor team in 1997, he was a fully cross-trained orbit determination/maneuver analyst and performed both duties. He said, "This doesn't seem like a big deal, but it hadn't been done very often in the past, so it was a unique opportunity for me."

He was fortunate enough to become involved with Mars Odyssey in the early stages of development and was thus responsible for all the navigation disciplines. Mase jokes, "I ended up as the navigation team lead, because at that time I was the only navigator on the project. I led a team of one." The team was staffed fully by the time Odyssey launched in April 2001, and more team members were added to support round-the-clock aerobraking operations following Odyssey's entry into Mars orbit. Now that the spacecraft has successfully concluded its aerobraking phase, the mapping mission has begun. Initial science results were announced on March 1, 2002.

The Life of a Navigator

Now that Mase's schedule has returned somewhat to normal, he was able to sit down and answer a few questions.

Question: Any sense of letdown now that aerobraking has been completed?

Answer: No, there's still plenty of work to be done, but my stress level has dropped noticeably. Actually, this is my first normal week - it was kind of strange having a free weekend.

Q: What have the last few years been like?

A: I joined the Odyssey program early on. It was really fun because I got to do everything navigators are responsible for. After the losses [of Mars Climate Orbiter and Polar Lander] in 1998, our project came under intense scrutiny, so that was when things really changed and the workload increased significantly. My responsibilities changed again when I became team lead, and it was kind of tough for me not to be as close to the hands-on analysis as I had been. But the team was great; we got the best navigators to fly this mission.

Q: What kind of qualities do navigators need, as opposed to other engineering specialties?

A: Navigation is kind of viewed as "a black art." Other disciplines actually build things. We never get to work with hardware. You have to be comfortable with and love math and physics. Orbital mechanics and orbit design is a unique field. There's just no other engineering discipline like it.

Q: You're from Naples, Florida. Did growing up in a state that spacecraft are launched from influence your choice of careers?

A: No, I was always interested in space. We did go to visit NASA's Kennedy Space Center when I was a kid. And we could see the space shuttle launch from our backyard, even though Naples is on the Gulf [of Mexico] side. But I think I would have been interested in space no matter where I grew up.

Q: You hold bachelor's and master's degrees in aeronautical and astronautical engineering from Purdue University in West Lafayette, Ind. Why Purdue, a long way from Florida's beaches?

A: Yeah (laughing), I went off to college with nothing but shorts and discovered winter the hard way! My friends had to take me shopping for winter clothes during Thanksgiving break. I applied to and was accepted into several engineering schools, but Purdue has a very prestigious aerospace engineering program, and I spent six years there.

Q: Did any college part-time job relate to or help you in your career?

A: Not really. I worked summers and Christmas as a pool cleaner at Nassau Pools in Naples. It was a great job for a college kid. They used to joke that I was the most highly educated pool cleaner ever.

Q: How did you decide to work at JPL?

A: I applied to lots of aerospace companies when I graduated in 1991, but the industry was really down at that time. After several months of searching, one of my professors who had worked for JPL provided me some contacts and references. Once I found the right connections, I was offered several opportunities [at JPL] and was fortunate to start on the Mars Observer navigation team.

Q: What are your interests away from work?

A: My number one interest is softball - I've been playing in the JPL leagues for 10 years. I also like mountain bike riding and body surfing, but I haven't had much time for them lately. I just bought a house in Pasadena, so that will probably take up what free time I have. It's right on the Rose Parade route, so I have a prime viewing location.