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Editor’s Note: University of North Dakota radio astronomer George Seielstad was recently selected to chair a national panel that will review future design and mission priorities that the National Aeronautics and Space Administration (NASA) is considering for its Deep Space Network (DSN). The ever-enthusiastic Dr. Seielstad—who is director of the UND Center for People and the Environment and professor of Earth System Science and Policy—also has had a lifelong interest in extraterrestrial life and formerly taught a course called “Life in the Universe” at UND.

In the following Q&A with Office of University Relations (OUR) science writer Juan Miguel Pedraza, Seielstad talks about the specifics of the DSN panel he chairs, NASA’s ongoing space exploration mission, and how his DSN role ties into his work at UND.

OUR: Let’s start with the basics—what is the Deep Space Network?

Seielstad: NASA describes its Deep Space Network (DSN) as “an international network of antennas that supports interplanetary spacecraft missions and radio and radar astronomy observations for the exploration of the solar system and the universe.” It receives signals from these probes and also sends commands to them, such as telling the Mars rovers where to go next.

This network supports selected Earth-orbiting missions. It comprises three deep-space communications facilities—at Goldstone, in California’s Mojave Desert; near Madrid, Spain; and near Canberra, Australia. They’re located roughly 120 degrees apart, which means at least one of them is always clearly receiving signals from this network. I think that this makes DSN the world’s largest scientific telecommunications system.

All those famous pictures you see from space—Saturn’s rings, Jupiter’s moons, volcanoes on Mars, the stunning images of galaxies—come in the form of digital data from all these missions that are captured and processed by DSN.

OUR: As a radio astronomer with a distinguished research and professional track record—you were at the California Institute of Technology's Owens Valley Radio Observatory and then at the National Radio Astronomy Observatory in Green Bank, West Virginia—you’ve been consulting with the DSN for several years. Now, you’re chairing a group that’s planning the network’s future. Why is this important? Why should we take note?

Seielstad: The work of this DSN panel I’m on is significant. NASA's Deep Space Network is on track—at a slow but steady speed—for a major new system. The new system, when completed, could serve research for several decades.

We want to do the job right, since its cost might be in the billion dollar range.

We want to improve, or upgrade, a system that already has a superb track record—in the 43 years that the network has been in operation, NASA has never lost a satellite due to a failure of the DSN. For critical events, such as launches and early operations, entry descent and landing, trajectory correction maneuvers, and encounters with celestial bodies such as planets and moons, DSN has a proven track record of success that exceeds 99 percent.

The challenge now is that the Apollo-era DSN hardware and software are aging. So NASA chartered this panel of space communications experts—the panel I’m chairing—to investigate the options for a Next Generation Deep Space Network (Next Generation DSN).

OUR: How does the panel plan to execute its primary mission?

Seielstad: The panel is expected to review the recommendations of the Space Communications Architecture Working Group regarding the Next Generation DSN. Second, we’re going to review the Jet Propulsion Laboratory’s (JPL’s) documentation related to the next generation DSN. (Editor’s note: JPL, based at the California Institute of Technology in Pasadena, is DSN’s hub.)

We also will conduct appropriate interviews and site visits, validate the Working Group’s findings, or propose alternative approaches. Finally, we are tasked with briefing NASA on the results of our work by the end of next month.

OUR: Where is your group leaning as far as key recommendations to NASA about DSN?

Seielstad: We’re taking a really fantastic system—for example, it’s still tracking and processing signals from Voyager, now about 10 billion miles away from Earth, past the outer reaches of our solar system—and improving it. We now have technologies that can support more science. That means sending back a lot more data at a much higher rate. What we’re seeing is that this project is going to higher levels of NASA, up to the federal Office of Management and Budget, all the way to Congress.

We want to build on what is already in place at the three DSN stations around the world. Basically, we’ll be expanding those stations.

But instead of one very large antenna, we want to build a brand new system—an array—of much smaller antennas that will work at higher frequencies, where you can get a bigger data rate. With a big antenna, if it goes down, you lose a significant part of your capacity, you’re basically out of business. But if a few antennas in an array fail, you still can keep working. We want to capture more accurate data from a variety of objects in the solar system.

I envision a time in the not-too-distant future when we’ll have constellations of satellites around planets or other space objects—a large asteroid or planetary moons, for example—and that will mean significantly more data. The DSN ground stations will have to keep up with these changes in space exploration strategies.

We’re looking at a fundamental change from building great big dishes.

Is this the right option? Well, we could keep the existing technology running. But the biggest dish in the system was built in 1966. Those big antennas are like any other large mechanical structure—you have to deal with metal fatigue, they wear down, and you’ve got to spend more and more time and money to keep them running.

It’s like keeping your 1966 car running—you can do it, but you’re putting more in as you go along. Maybe you’d be better off investing in a newer, more efficient car. You can keep a 1966 car running but you’d be smarter to get a newer, better car. I definitely think we’re at that point with the DSN.

OUR: Besides being a singular professional honor, what does your work on the DSN panel—a select group of top U.S. space scientists and engineers that picked you for the job—do for you and for the University?

Seielstad: First, I’d say that it significantly enhances my teaching and advisory roles at UND. Yes, this kind of stuff takes up lots of time and energy, but I learn an enormous amount when I participate in these activities.

Editor’s note: For a detailed look at DSN, see http://deepspace.jpl.nasa.gov, NASA’s DSN Web site and http://deepspace.jpl.nasa.gov/dsn/movies/CommThroughSpaceCap.mov for a QuickTime movie about DSN.