Dr. Z has left the building.
After six years, Thomas Zurbuchen concluded his tenure as the head of NASA’s science missions at the end of 2022.
During his time there, he earned his single-letter nickname while presiding over some of the agency’s biggest successes in the exploration of the solar system and the universe: the long-delayed launch of the James Webb Space Telescope; the landing on Mars of the Perseverance rover, which was accompanied by the Ingenuity helicopter; and the slamming of the DART spacecraft into a small asteroid, demonstrating a technique that could be used if a space rock were discovered on a collision course with Earth.
“Immensely proud of what we’ve achieved as a team,” Dr. Zurbuchen said in an interview. “Also sad to leave the team that is here, the job that I’ve really loved.”
Dr. Zurbuchen held the job of associate administrator for the science directorate for a longer continuous stretch than any of his predecessors.
It is a job that is akin to running a space agency within a space agency. NASA’s science directorate has a budget — $7.8 billion for the current fiscal year — that is larger than that of the entire European Space Agency. In addition to planetary science and astrophysics, the directorate also oversees earth science research.
For Dr. Zurbuchen, it was time to leave.
He said it was important for the science directorate to be led by someone who was pushing new ideas, as NASA had already implemented many of his. While he still enjoyed the job, he said that in the seventh year of putting together and implementing budgets, he was learning less. “Those two things made me think about, ‘How do I find the right exit?’” he said.
But he is gone before seeing whether one of his biggest bets — higher-risk, lower-cost collaborations with small private companies to send science instruments to the moon — will pay off.
The program is known as Commercial Lunar Payload Services, or CLPS. That continued a shift at NASA, similar to how it now relies on companies like SpaceX to provide transportation of astronauts and cargo to the space station.
When CLPS was announced in 2018, Dr. Zurbuchen said NASA was aiming to take “shots on goal,” a soccer or hockey metaphor that acknowledged that not every shot scores and that not every CLPS mission would successfully arrive at its destination intact.
NASA officials said then that the first CLPS mission could launch as soon as the following year, in 2019, and the aim was to fly two CLPS missions each year.
But today none of them have yet reached the launchpad. Instead of eight missions already, there are still zero shots on goal.
“CLPS has not proven itself,” Dr. Zurbuchen conceded, although two launches are on the schedule for 2023. One lander is from Intuitive Machines of Houston, to be launched on top of a SpaceX Falcon 9 rocket; the other lander is from Astrobotic Technology of Pittsburgh, riding on the maiden flight of United Launch Alliance’s new Vulcan Centaur rocket.
If both companies succeed on their first tries, NASA officials will certainly celebrate. But except for successes by China, all of the robotic moon landing attempts in recent years have crashed. What if one of the CLPS missions fails? Or both?
The key, he said, is to take smart risks, and not to panic if not all of the risks pay off. “The fastest way of turning off all innovation is to punish the people who do listen to you and actually are trying new things,” Dr. Zurbuchen said. “Let’s not kill them.”
The next associate administrator would have to decide how to adjust course.
“After how many CLPS failures do we say, ‘Hey, it’s not working?’” Dr. Zurbuchen said. “It’s an experiment, right? There is no way to get to the moon otherwise for substantially less than a billion bucks. And that’s what we tried to break, that cost of entry.”
Dr. Zurbuchen was in some ways an unusual choice for the job. A native of Switzerland, he earned his Ph.D. at the University of Bern and completed considerable research on solar science. He had led the development of one of the instruments on NASA’s Messenger spacecraft that had orbited Mercury, but Dr. Zurbuchen had never worked at NASA.
In 2016, Dr. Zurbuchen, then a professor at the University of Michigan and founding director of the university’s Center for Entrepreneurship, got a phone call from John Grunsfeld, then the NASA associate administrator for science. Dr. Grunsfeld said he was planning to step down and told Dr. Zurbuchen that he should apply for the position.
In an interview, Dr. Grunsfeld said he had not been involved in selecting his successor, “but I wanted to make sure that there was a good pool of candidates.”
He thought candidates should “share some of the philosophy for new concepts and advancing science that I have,” Dr. Grunsfeld said.
NASA’s science directorate runs big projects like the James Webb Space Telescope with budgets that run into the billions of dollars. But there were also scientific opportunities for using tiny CubeSats. “I knew that he was interested in those things,” Dr. Grunsfeld said.
Dr. Grunsfeld announced his retirement from NASA in April 2016. In October of that year, Dr. Zurbuchen was named as the new associate administrator for science.
He had a few goals coming into the job. “Rule 1,” he said, “is don’t break it.”
But he also felt that NASA leaders could do a better job. “I think it’s always easy to say, ‘Space is hard — that’s why we have management problems,’” Dr. Zurbuchen said. “But I just don’t think it’s a carte blanche. I think we should do our best job so if we get surprised, we can actually explain why we missed it.”
How NASA executed its ambitious missions “was really, really important because it actually gave trust in how we deal with taxpayers’ money,” he said. “Within just a few months, I terminated the first mission.”
The was the Radiation Budget Instrument, which was to have measured sunlight reflecting off the Earth. The project experienced technical problems and spiraling costs. “What I really felt was important is that we looked at the opportunity set and basically asked, ‘Is there a way to get more science or more science per dollar?’” Dr. Zurbuchen said.
For earth science data, NASA now buys much of it from commercial satellite companies instead of building its own spacecraft. “Close to 1,500 scientists within the United States are doing research on these data,” Dr. Zurbuchen said. “Totally new way of doing that.”
Not all of the new ways of doing business have worked. For example, NASA selected some missions that were to put scientific devices on commercial communication satellites headed to geostationary orbit, at altitudes of more than 22,000 miles. But with a shift in the telecommunications industry, there are fewer geostationary satellites being launched now. “We basically lost our rides,” Dr. Zurbuchen said. “So our commercial partnerships did not work. We’re sitting on the ground.”
The biggest challenge was getting the James Webb Space Telescope, which was going awry with technical and management problems, back on track. “Basically asking the question, ‘Is it worth finishing?’” Dr. Zurbuchen said. “Not knowing what the answer was and going through the process was really, really hard.”
The Webb telescope was finally launched in December 2021, and it provided Dr. Zurbuchen’s favorite moment, too, when he saw the telescope’s first deep-space image before President Biden released it publicly.
“At that point, there were only a couple of handfuls of humans that had seen that — with a telescope that we built and struggled with enormously,” Dr. Zurbuchen said. “It was a quintessential moment, both of human achievement but also history made, NASA style.”