Paul Spudis, whose passion for lunar science and resource utilization is legendary, passed away today. He was 66. NASA Administrator Jim Bridenstine, who knew him well, emotionally broke the news at a meeting of the NASA Advisory Council (NAC), which then observed a moment of silence. Spudis is well known throughout the space community and many are expressing their condolences.

Bridenstine interrupted a discussion of NASA’s lunar exploration plans to inform the Council of the sad news. He commented that Spudis would be delighted to know that NAC was discussing lunar exploration, which is back in the limelight after many years of being on the sidelines while NASA focused on sending astronauts to an asteroid and then to Mars. Spudis indefatigably argued for humans to return to the Moon to conduct science and take advantage of lunar resources.

NASA Associate Administrator for Human Exploration and Operations, Bill Gerstenmaier, who was giving the presentation at the time, called the news “hard” and noted that many people in the room knew Spudis and how “passionate” he was about the Moon. NAC Chairman Lester Lyles was similarly struck, noting that he and Spudis served together on President George W. Bush’s Commission on the Implementation of U.S. Space Exploration Policy.

Bridenstine later tweeted his personal reflections.

I’m saddened to hear of the passing of Paul Spudis. Paul had a profound impact on my life and his loss will be felt throughout the space community. My prayers are with his family. — Jim Bridenstine (@JimBridenstine) August 29, 2018



Spudis was a geologist who spent his career at the U.S. Geological Survey, the Lunar and Planetary Institute (LPI), and Johns Hopkins University Applied Physics Lab. Since 2008, he had been a senior staff scientist at LPI, and since 2013, also Chief Scientist of Moon Express, a private company that is building small landers/rovers for the Moon. Moon Express co-founder and CEO Bob Richards was among the first to tweet condolences.

So saddened by the loss of a dear friend and pillar of our lunar science community. Truly fearless and poignant, Paul Spudis will not be replaceable, but our future is brighter because of his relentless efforts. Thank you Paul. Ad luna.https://t.co/oLXaXv9vVs pic.twitter.com/f0U9WGZMf1 — Bob Richards ? (@Bob_Richards) August 29, 2018

Spudis wrote four books, including The Once and Future Moon (1996) and The Value of the Moon: How to Explore, Live and Prosper in Space Using the Moon’s Resources (2016). He co-authored another three, was widely published in popular magazines like the Smithsonian’s Air & Space as well as refereed journals, and authored the Once and Future Moon blog for Air & Space magazine. He served on advisory committees for President George H.W. Bush and President George W. Bush on future U.S. human exploration plans (the Synthesis Group and, as noted above, the Presidential Commission on the Implementation of U.S. Space Exploration Policy, respectively).

He was part of the scientific teams for several lunar orbiters including the DOD-NASA Clementine mission, India’s Chandrayaan-1, and NASA’s Lunar Reconnaissance Orbiter (LRO), which has been orbiting the Moon since 2009.

In a 2014 Houston Chronicle article by Eric Berger, which Berger shared via tweet today, Spudis told the story of how his fascination with the Moon was inspired by the Apollo 15 crew and led him to change his career plans from engineering to geology.

Then there’s this anecdote he shared with me, in 2014, about himself and Apollo 15 commander Dave Scott.https://t.co/rul72VLGdg pic.twitter.com/45knAcsh1B — Eric Berger (@SciGuySpace) August 29, 2018

Space reporter and author Leonard David said via email that —

“The loss of Paul Spudis is a loss to the future, for those now engaged in reviving exploration of the Moon. Paul was a personal friend, science wizard, a visionary and in-your-face when you didn’t capitalize the “m” and make it Moon. His talents and insightful thoughts about the Moon were exceptional. I’ll miss him dearly.” — Leonard David

Tributes from many in the lunar science community are posted on David’s blog.

Note: This article has been updated.