Audio collage begins.

STEVE WALDHERR

I’m the first point of contact for anybody wanting to use DSN…

KRIS ANGKASA

Ultimately, we ensure that the DSN requirements for a specific project or a specific mission are met.

STEVE WALDHERR

And the [facial] expression of the principal investigator, when they opened up the capsule was just worth it all: like a kid in a candy shop.

KATHLEEN HARMON

They’re the first spacecraft that humans have tracked that have actually left our solar system, gone into interstellar space, and ­– believe it or not ­­– we can still talk to them. To me, that’s almost unbelievable…

KRIS ANGKASA

I so appreciate the opportunities that I have at JPL.

KATHLEEN HARMON

DSN was the vehicle by which they could return data to Earth. Otherwise, they wouldn’t have been able to do it.

Audio collage ends

NARRATOR

What does it take to communicate with deep space? We’ve covered infrastructure: the physical systems that capture radio waves flowing from spacecraft across the solar system. We’ve covered architecture, following the Sun around the world as engineers pass control of the network between stations. What’s left?

STEPHEN LICHTEN

I’m Stephen Lichten and I’m a system manager on the technical staff of JPL’s Interplanetary Network Directorate, which… oversees the Deep Space Network among some other programs as well.

NARRATOR

In his long career at JPL, Steve has engineered and optimized communications and navigation systems on both the network and mission side of things.

STEPHEN LICHTEN

I’ve worked here over 30 years. So, I’ve done lots of different things.

I think my, my favorite memory was during the Mars Science Laboratory – the Curiosity rover – when it landed on Mars in 2012. I was then the division manager of the division that delivered the telecom subsystems for the cruise and descent stages, as well as for the rover itself.

And in addition, we built and delivered the landing radar, which was a first-of-a-kind, rather complex, single string system that had to work or the mission would fail… The radar turned out to be very challenging to build, test, and deliver.

And I was working on landing night in 2012 as a host to a roomful of former lab directors and VIPs. I was explaining to them how the descent to the surface was proceeding as it happened. But deep inside, I was very worried about our radar because I knew it had to work flawlessly.

And then in the middle of the briefing, I noticed the spacecraft had sent a signal which we received in our Deep Space Network. That signal led the flight director to announce, “Radar reliable,” which told me right away that it was on and working as planned. So, for me, that was kind of an electrifying moment. I was – it was a very big deal for NASA and for me personally. And then the rover landed safely.

The Mars 2020 rover also landed safely, this time in February of 2021, with a copy of this very same landing radar.

NARRATOR

In his current role as Deep Space Network system manager, Steve works on a wide variety of initiatives aimed at preserving and enhancing DSN capabilities.

STEPHEN LICHTEN

I’m currently very involved in a number of technical studies, performance analysis, systems analysis, and risk analysis pertaining to the Deep Space Network… And one of the areas of focus I’m working on is the Deep Space Network loading and scheduling.

NARRATOR

With physical infrastructure in place and operational architecture outlined, scheduling is the missing piece of Deep Space Network operations.

STEPHEN LICHTEN

Right now, we’re supporting between 35 and 40. It varies from year to year, but it’s about three dozen missions… The missions currently are everywhere in the solar system and beyond.

NARRATOR

The Deep Space Network needs service agreements with each of these missions – agreements that must be executed by schedulers who supply them with promised services.

STEPHEN LICHTEN

There’s a team of schedulers for the DSN, and they work closely with their mission scheduler representatives. So, each mission has a representative – or more than one in some cases – and they regularly meet to understand each mission’s most important needs and how they can be met with the DSN antenna allocations.

It’s partly a manual process and part automated, but it’s one that incorporates a lot of negotiation between all the parties that are involved.

NARRATOR

With unlimited resources, scheduling wouldn’t be too difficult. However, the Deep Space Network has a limited number of antennas to support a growing number of missions.

STEPHEN LICHTEN

It’s a considerable challenge, because the requests for DSN intended time exceed what is available by typically 25%, or as much as 50%, or even more. So, a lot of the scheduling complexity stems from the fact that not only are missions asking for more time than we actually have, but… there are three dozen missions all over the solar system, all different directions… plus, each antenna has scheduled maintenance roughly 15% of the time, and this all has to get factored into the overarching schedule.

NARRATOR

How can the DSN make up that missing availability?

STEPHEN LICHTEN

We can’t make it up. It’s physically impossible. So, we work with the missions to understand… which parts of the passes or which passes are most important to them and we make sure that their most critical needs get met…

We have lots of knobs we can turn and… we find a way for them to accomplish what they are trying to accomplish but with less hours on the DSN antennas. And there are various ways we can do that. We understand the ins and outs of all the services and capabilities of the antennas. The missions often don’t have that kind of insight – deep knowledge – so we help them meet their needs with possibly less time than what they actually thought they needed.

NARRATOR

Thanks to the deep knowledge and experience of network personnel, they do a very good job of meeting customer needs with the efficient and effective services.

STEPHEN LICHTEN

The DSN is already very reliable, the requirement is 95% for the successful passes, and our actual performance is closer to 99%.

NARRATION

The need for more service hours also drives innovative new capabilities that allow the network to support more missions with the same number of antennas. DSN project manager, Brad Arnold:

BRAD ARNOLD

We’ve enabled something that we call multiple spacecraft per aperture. It’s not an uncommon thing that happens in terrestrial systems, and we went ahead and adapted that to the DSN.

Now we only need to point one antenna, and as long as [the spacecraft] are each on different frequencies, we can sort them out on the ground… And so now we can track… four spacecraft with one antenna. And that frees up three other antennas to go point somewhere else in space.

NARRATOR

In today’s episode of our Deep Space Network season of the podcast, we’ll meet some of the Mission Interface Managers, or MIMs, responsible for furnishing missions with the services they need throughout the mission lifecycle, from initial mission concept idea through proposal and development to assembly, and launch and into operations. We’ll journey through the various mission phases: from phase A, where scientists and engineers conceptualize missions; through phases B, C, and D, where they build the spacecraft; to phase E, where the spacecraft enters operations.

The MIMs will also highlight some of their favorite missions they’ve worked on. Along the way, we’ll learn what it takes to negotiate services with a world-class network like the DSN.

The Invisible Network theme.

I’m Danny Baird. This is “The Invisible Network.”

…

A collage of historical audio

PRESIDENT JOHN F. KENNEDY

We choose to go to the Moon in this decade…

NEIL ARMSTRONG(Apollo 11)

That’s one small step for man…

COMMENTATOR(Voyager Launch)

We have ignition, and we have lift off!

CHILD FROM VOYAGER GOLDEN RECORDS

Hello from the children of planet earth…

COMMENTATOR(Cassini Launch)

Three… two… one… and liftoff, of the Cassini spacecraft…

COMMENTATOR(Perseverance Landing)

Touchdown confirmed, Perseverance safely on the surface of Mars…

Theme music fades.

…

KRIS ANGKASA

My name is Kris Angkasa. I am a Mission Interface Manager for the Deep Space Network… Ultimately, we ensure that the DSN requirements for a specific project or a specific mission are met.

We have a number of missions to take care of. And some of them [are] in Phase A, which is very early on – you know – still in proposal stage… and then it goes to B, C, D, and E is for operations. So, E is what’s already on Mars, what’s already flying, and so on and so forth…

For phase A through D missions, we do compatibility testing… that can be done with a spacecraft or with a single radio of the spacecraft, either at the DSN’s facility, which is called DTF 21, in Monrovia, California, or we also have a trailer that you can haul to the missions…

To make sure that the DSN requirements are still valid… maybe a few weeks before launch, we do have a DSN Test Facility at the Cape… and we do some of the DSN compatibility reverification testing there as well.

And then for phase A through D missions, we hold reviews throughout the years. And the ultimate one is… called the DSN Mission Event Readiness Review, DSN MERR. And a team [from] the DSN is pulled together to… make sure that all of the DSN requirements are met.

For Phase E operations, we support critical events such as launch, Mars landing, Jupiter orbit insertion, as well as a few spacecraft early deployment activities, such as the first time [the] Ingenuity helicopter was flown on Mars. We support that also with an elevated level of support from the DSN.

For me, my responsibility is flavored between the NASA missions and ESA missions. So, for the NASA missions, I support Mars 2020, Insight, Curiosity rover, Chandra, and Lucy mission.

I so appreciate the opportunities that I have at JPL… I’m very thankful for JPL [giving] me the opportunity to basically move around to seek out my interest… Now I’m here and I’m happy to serve both the DSN and the project at the same time as a MIM.

…

STEVE WALDHERR

I’m Stefan Waldherr. I go by Steve. I’m a Mission Interface Manager for the DSN Support and Commitments office… I was working the Deep Space Network starting in February – let’s see – February 1981.

At Goldstone, when I started in 1981, we actually were still sending commands to the Viking lander before we lost it. I’ve also worked in the darkroom – or control room­ – at JPL, supporting missions such as Voyager. One of my big missions – JPL missions: I supported Cassini, and also death of Cassini, or the spiral into the surface.

40 years in the Deep Space Network… I’ve done everything from station operations, to darkroom operations in the control center, to software acceptance of the tracking software that we use at the station, to network operations planning engineer on the contract side.

[As the] Mission Interface Manager… I’m the first point of contact for anybody wanting to use DSN… What we do is help align customers’ service requests, with DSN standard services. And most of the time, when I bring a mission on board to the Deep Space Network, the MIM is… from pre-launch, all the way to end the mission…

I think it’s very satisfying, building that rapport with other people in this field. And they could be a radio scientist, they could be a navigator, they could be a plasma scientist, and it doesn’t matter. It’s all interesting because I learn from them.

I’ve worked with the French space agency, German space agency, European Space Agency. I worked Japanese missions for a couple of years. As far as missions goes, I’ve worked quite a few of them…

One of my favorite missions is Stardust, a comet sample return. And that was interesting… Stardust, we had a… comet encounter in January 2004. The sample return was in 2006. The principal investigator out of Washington University Dr. Brownlee [was a] very down to Earth person, and we got to meet with him, see his science objectives.

Stardust [had] a tennis-sized racket with aerogel in it to capture high velocity particles, because the [difference in] velocity between the spacecraft and the coma of the comet are pretty high. And we were hoping to catch just barely microscopic particles from the coma – or the tail of the coma actually – for the encounter, and in the sample return, we actually were able to get BB-sized, garnet-looking particles.

And the [facial] expression of the principal investigator, when they opened up the capsule was just worth it all: like a kid in a candy shop.

Pre-encounter, we had the scientists [on] one side room, engineers on the other. How close do we get to the comet itself?

And the engineer says, “Not too close, because the particles will damage the spacecraft and the camera.”

And the scientist says, “No. No. No. We want to get close. We… want particles.”

Anyway, during the actual comet encounter – I can’t recall, the distance we settled on ­–…there’s a particle counter – impact counter ­­– on the spacecraft. And the comet itself had craters and jets of particles would stream out from the edge of the crater as the comet rotated – kind of like a spin wheel – and we could see it on the particle counter.

To me, that was one of my most amazing moments: the scientists arguing with the engineers, “How close do we get?”

We dropped the sample return in Dugway… Proving Grounds in Utah. We actually got to go to the site, visit it. You know, everybody picked where it’s going to… parachute down… Watching it come in through the upper atmosphere, watching the drogue chute come out, and watching it land… after the years of work I put on [the mission], was very satisfying.

…

KATHLEEN HARMON

My name is Kathleen Harmon, and I’m a Mission Interface Manager, or MIM, for NASA’s Deep Space Network…

I serve as an interface between the Deep Space Network or DSN, and the customers of the DSN. It’s really a systems engineering role at NASA, and it focuses on: understanding what the mission’s requirements are, and then defining and documenting the interfaces between DSN and the mission, and then verifying and validating those so that everything is in place prior to launch, so we can support the mission.

As much as possible, we stick with standards… if we had everyone make up their own way of doing things, that wouldn’t work well, because we couldn’t support so many. So, we do follow standards. In this case, CCSDS is the Consultative Committee for Space Data Systems.

We produce a document called the DSN Service Agreement. It’s a service level agreement that just says, “The DSN agrees to provide these services.”

…The main ones are telemetry, tracking, and command. Most missions want that. But there are other services… radio science, and some other ones. And we get all those agreements ironed out during the development phase.

Then the really exciting and busy phase is the integration and test phase, which is putting all the different parts of the mission together to get it ready to launch… So, we run a big test called an RF compat test – “RF” means radio frequency, “compat” is compatibility ­– to make sure that the data rates they use, the frequencies they use, the modulations they use, etc. all agree with the DSN standards…

When I first started in this job, I didn’t know too much about DSN. I knew about it, but I hadn’t worked in detail in it.

But they said, “Kathleen, we have a spacecraft called Juno that’s about to arrive at Jupiter, and it has a very important maneuver called Jupiter Orbit Insertion or JOI, which is where they take this really powerful engine onboard and burn it to make sure [Juno] stops hurtling through the solar system and goes into orbit around Jupiter. It’s a very important burn. And obviously, if it didn’t work, and Juno flew by Jupiter, then that would be the end of the mission.”

So, it was a very important burn.

So, the mission was very anxious to get all of the coverage for this event [that] it could. And DSN provides antennas on the ground that provide information about how that burn is going and all the information they need.

So, I was told to work on that and coordinate the DSN support for that. And we had actually seven… antennas on the ground – a few in California and a few over in Australia – that supported that event, which was on July 4, 2016.

And so, when that engine burned, Juno did go successfully into orbit around Jupiter. And it’s been a wonderful mission. It’s actually an extended mission. It finished all its main objectives for its prime mission and all that’s due to DSN being able to communicate with it.

You might have seen some of the amazing, wonderful photos – they’re really like art to see some of those pictures ­–…that spacecraft is capturing.

I also had the privilege of working on the Voyager spacecraft… Those were launched in the 70s. So, for me, just to know they’re still alive and going. And in fact, as I worked in the DSN, that both of them – one after the other – left the solar system.

They’re the first spacecraft that humans have tracked that have actually left our solar system, gone into interstellar space, and ­– believe it or not ­­– we can still talk to them. To me, that’s almost unbelievable…

The final one I’ll mention is the New Horizons spacecraft, which you may have heard of. It flew by Pluto a number of years ago and took some amazing pictures.

Well, I came on board after that. So, when I came, the Pluto mission was done, but… the spacecraft was very healthy, had lots of fuel on board. So, the mission went to NASA headquarters and said, “Hey, why don’t we do another flyby even farther than Pluto.”

They got approved by NASA Headquarters, and they flew by an object deep in the Kuiper Belt – and just so you know – from Pluto and beyond, it’s just an area of space called the Kuiper Belt, where there are all sorts of really primordial objects from when the solar system first started.

They’re very dark objects, and we don’t know a lot about them just because they’re so far away. And so, to be able to have a spacecraft fly by – do a close up fly by – and take images, and spectra, and all sorts of radar observations of it was just an amazing opportunity.

So, NASA approved that, and the DSN supported that spacecraft. So, when it flew by – that was on New Year’s Eve, I believe, 2018 or so –…DSN was there to make sure… the spacecraft could put all of its last minute… navigation corrections into the system so that it didn’t miss this target. And it did indeed fly by and take amazing pictures of this dark object ­– now called Arrokoth – we called it Ultima Thule at the time.

But there were some amazing pictures taken a lot of science papers published on it. And… the DSN was the vehicle by which they could return data to Earth. Otherwise, they wouldn’t have been able to do it.

…

NARRATOR

Kathleen also has high-profile human spaceflight missions in her portfolio. She’s been assigned the task of supplying the Artemis missions to the Moon with Deep Space Network services.

KATHLEEN HARMON

After I did many science missions, my boss came up to me said, “You know what, we need someone to take over the human spaceflight support that the DSN will be doing. Would you like to do it?”

And of course, I said, “Yes, that sounds fabulous.”

I was actually alive when Apollo happened. I was a very young person, but I remember the Apollo missions – especially growing up the space shuttle ones. But for me to work on the Artemis missions, which are the current set of human spaceflight missions [to the Moon]. I couldn’t say no to that opportunity.

So, I said, “Yes, I would love to work on human spaceflight.”

NARRATOR

For Artemis, it’s all hands on deck. Both of NASA’s Space Communications and Navigation program networks will support.

KATHLEEN HARMON

I work with the Deep Space Network, but the Near Space Network: we are like… siblings, sisters or brothers. We work together and we all want the mission to succeed…

When the spacecraft first launches out of Kennedy Space Center… The first stations that the spacecraft will communicate with… are located here in Florida. There’s one actually on site, here’s called Kennedy Uplink Station, or KUS, it’s run by the NSN…

Once it keeps going higher and higher, it’ll go through other network elements, eventually getting up to the space relay… the spacecraft called TDRS:… Tracking [and] Data Relay Satellite. And then there’s a handoff.

I like to think of it [like] when you see a relay race and one runner hands off the baton to the next runner. That’s what we have here. The [Near Space] Network will hand the baton off to the DSN after the spacecraft exceeds that geostationary altitude where the TDRS satellites are.

And from then on, DSN will be prime throughout Artemis’ mission around the Moon.

Now once it returns – comes back from [the] Moon ­– we will do a reverse handoff, where once the spacecraft gets lower in the atmosphere, it will stop communicating with DSN and we’ll start communicating with TDRS…

NARRATOR

As I interviewed Kathleen for this episode, she was on site at NASA’s Kennedy Space Center in Florida supporting tests on the Orion spacecraft, which will ferry NASA astronauts to the Moon for the first time since Apollo. She was there with representatives from NASA’s Near Space Network, based at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, making sure that all the network elements are ready to support the upcoming Artemis I mission, an uncrewed test of Orion and the Space Launch System, NASA’s powerful new rocket, in preparation for the crewed Artemis II mission.

KATHLEEN HARMON

We work very closely with our partners at Goddard and the NSN. And we’re all one team. And we’re all working together to make the mission succeed.

…

NARRATOR

Looking to the future, the DSN is building new antennas to service the growing number of deep space missions. The network is also investing in technologies like optical communications, which will open the infrared spectrum to space users seeking high data rate links. There are also network protocols like Delay/Disruption Tolerant Networking, or DTN, that will extend internet-like capabilities to space.

We’ll cover these future capabilities in the final episode of the season, but Steve Lichten noted some scheduling-specific innovations that might make finding the antenna time to support missions easier than ever:

STEVE LICHTEN

The scheduling process is… going to be become more automated, but that’s actually very challenging. Because if you compare deep space mission scheduling to, say the Earth orbiter mission scheduling: Earth orbiters, their geometry basically repeats all the time. Many, many times. Multiple times during the day.

Whereas in deep space, things are moving in a unique way, and the planets move, and over a period of years, they actually don’t repeat the location, or relative geometrical arrangement. So, it’s kind of unique. It’s harder to automate, but it is possible. And so, we’re making new tools to become more automated in that respect.

We already have automated tools that look for and fill existing gaps in DSN antenna schedules… That’s one way we can help accommodate missions that aren’t getting all the antenna time that they want.

And other innovations will include something that we call “demand access,” where a spacecraft won’t have to have regularly scheduled passes, but they’ll send down a beacon signal that tells us on the ground that a spacecraft needs to pass, or it needs help, or it needs to send data down, or needs something. And then we would automatically schedule a pass to accommodate that spacecraft.

…

The Invisible Network theme.

NARRATOR

Each Deep Space Network Mission Interface Manager touches so many missions as a part of their work. Their storied careers are testament to the critical nature of space communications services. No spaceborne mission would leave Earth without them.

Philip Baldwin, SCaN program executive:

PHILIP BALDWIN

One thing about NASA you will learn is that: you look at all the amazing people at NASA and you’re just like, “Wow, like, how am I even here…” You will always be awed by the talent that we have at NASA.

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NARRATOR

Thank you for listening. Do you want to connect with us? The Invisible Network team is collecting questions about NASA’s Deep Space Network from listeners like you! We’re putting together a panel of NASA experts from across the Space Communications and Navigation community to answer your questions.

If you would like to participate, navigate over to NASA SCaN on Twitter or Facebook and ask your question using the hashtag AskSCaN. That’s @ NASA SCaN, N-A-S-A-S-C-A-N, on social media, with the hashtag AskSCaN, A-S-K-S-C-A-N.

This Deep Space Network-focused season of “The Invisible Network” debuted in summer of 2022. Developed by NASA’s Jet Propulsion Laboratory in Southern California, the Deep Space Network is managed by JPL with funding and strategic oversight from the Space Communications and Navigation, or SCaN, program at NASA Headquarters in Washington, D.C.

This podcast is produced by SCaN at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, with episodes written and recorded by me, Danny Baird. Editorial support is provided by Katherine Schauer and JPL’s Laurance Fauconnet. Our public affairs officer is Lora Bleacher.

Special thanks to Fall 2021 interns Julia Adde and Nate Thomas, Barbara Adde, SCaN Policy and Strategic Communications director, and all those who have lent their time, talent, and expertise to making “The Invisible Network” a reality. Be sure to rate, review, and follow the show wherever you get your podcasts.

For transcripts of episodes, visit NASA.gov/invisible. To learn more about the vital role that space communications plays in NASA’s mission, visit NASA.gov/SCaN. For more NASA podcast offerings, visit NASA.gov/podcasts. There, you can check out “On a Mission,” the official podcast of NASA’s Jet Propulsion Laboratory.