Edward C. Stone | |
|---|---|
 Stone in 1981 | |
| 7th Director of theJet Propulsion Laboratory | |
| In office January 1, 1991 – April 30, 2001 | |
| Preceded by | Lew Allen |
| Succeeded by | Charles Elachi |
| Personal details | |
| Born | Edward Carroll Stone Jr. (1936-01-23)January 23, 1936 Knoxville, Iowa, U.S. |
| Died | June 9, 2024 (2024-06-10) (aged 88) Pasadena, California, U.S. |
| Known for | JPL director and Voyager scientist |
| Scientific career | |
| Alma mater | University of Chicago (MS,PhD) |
| Fields | Space physics |
| Thesis | Low Energy Cosmic-Ray Protons (1964) |
| Doctoral advisor | John A. Simpson |
| Doctoral students | Neil Gehrels[1] Jamie Sue Rankin[2] |
Edward Carroll Stone Jr. (January 23, 1936 – June 9, 2024) was an American space physicist, professor of physics at theCalifornia Institute of Technology, and director of theNASAJet Propulsion Laboratory (JPL) from 1991 to 2001. He was the project scientist of theVoyager program, which sent two spacecraft to the outer Solar System's giant planets and became the first spacecraft to enter interstellar space.
Stone led the Voyager mission for 50 years, from 1972 until his retirement in 2022, overseeing the spacecraft's encounters with Jupiter (1979), Saturn (1980–1981), Uranus (1986) and Neptune (1989). Under his leadership, the mission discovered active volcanism on Jupiter's moon Io, new moons and ring systems. The Voyagers continued beyond the planets to cross the heliopause and enter the interstellar medium, with Voyager 1 becoming the first spacecraft to leave the Solar System in 2012, followed by Voyager 2 in 2018. The Voyager mission became the longest-running NASA mission, with Stone being its face and advocate.
As JPL director, Stone oversaw the successful launches ofMars Pathfinder with the first Mars roverSojourner,Mars Global Surveyor,Cassini–Huygens and other missions during NASA's"faster, better, cheaper" era. Throughout his career, he served as principal investigator on nine NASA spacecraft missions, includingSAMPEX, theAdvanced Composition Explorer and scientific instruments on theGalileo andSTEREO missions.
Stone's contributions to space science earned him theNational Medal of Science (1991), theNASA Distinguished Public Service Medal (2013), and theShaw Prize in Astronomy (2019). He was elected to theNational Academy of Sciences in 1984 and served key roles in establishing major astronomical facilities, including overseeing the creation of theLaser Interferometer Gravitational-Wave Observatory (LIGO) during his tenure as chair of Caltech's Division of Physics, Mathematics and Astronomy, and supervising the construction of theW. M. Keck Observatory.
Edward Carroll Stone Jr. was born inKnoxville, Iowa, on January 23, 1936, to Edward Carroll Stone Sr., a construction superintendent, and Ferne Elizabeth Stone. He was the eldest of two sons.[3] Stone grew up inBurlington. While at school, he worked at aJ.C. Penney department store, and was a member of the Burlington Municipal Band playingFrench horn.[4]
Stone studied atBurlington Junior College in Iowa, and continued his education at theUniversity of Chicago where he earned hisM.S. (1959) andPh.D. (1964) degrees in physics.[3] Initially, he planned to studynuclear physics, but became interested inspace physics after the launch of the SovietSputnik in 1957.[5] Stone began astrophysics research in 1961, working on a cosmic-ray telescope carried byDiscoverer 36 spy satellite. He worked on it under the cosmic rays researcherJohn A. Simpson's supervision.[6][4] The experiment became his PhD thesis, titledLow energy cosmic-ray protons.[7] While in Chicago, Stone also worked withEugene Parker; he said later that "Parker taught me how to reduce a problem to its nuts and bolts, to a picture."[8]
Stone moved to Caltech to work on space physics withRochus Eugen Vogt in 1964,[9] and helped him to establish theSpace Radiation Laboratory.[10] He became a full faculty member in 1967.[11] In 1976, Stone was named professor of physics, later the David Morrisroe Professor of Physics,[12] and was chair of the Division of Physics, Mathematics, and Astronomy from 1983 to 1988;[11] during his tenure he oversaw the establishment of theLaser Interferometer Gravitational-Wave Observatory (LIGO).[13] He had also served as director of the Caltech Space Radiation Laboratory, and as vice president for Astronomical Facilities. He was the vice-chair of theThirty Meter Telescope Board of Directors.[14] He also served on the board of theCalifornia Association for Research in Astronomy (CARA) for nearly 25 years, and oversaw the construction of theW. M. Keck Observatory.[13] He was also aW. M. Keck Foundation director, and chaired the Keck Foundation's Science and Engineering Committee for 24 years.[15]
In 1964,Gary Flandro, a summer student at JPL, found out that the rare planetary alignment of the giant planets allows a mission he called "the Grand Tour". Such alignment occurs every 175 years; Flandro calculated that the best option was to launch spacecraft in 1977.Gravity assist maneuvers were already known, but according to Flandro he was the first to notice the opportunity to visit the giant planets.[a] NASA was reluctant to finance the proposed mission of four spacecraft, but it eventually transformed into theVoyager program.[16]
In 1972, Stone became the project scientist for the Voyager program that sent two space probes to the giant planets in the outerSolar System.[4] He was invited for the position byHarris "Bud" Schurmeier, the mission's first project manager;[16][17] according to Schurmeier, Stone was proposed as the project scientist by Rochus Vogt, who was involved into the Grand Tour mission planning from the start. Stone himself was reluctant at first: as a scientist, he didn't want to sacrifice a lot of time for administrative work.[18][b] Stone was also theprincipal investigator for theCosmic Ray Subsystem experiment on both Voyager spacecraft.[20]
Stone supervised the work of 11 teams of about 200 scientists;[21] he organized "the clique-like teams" and work groups for key points of interest, "moons, rings, atmosphere and magnetosphere". Stone had the final word on observation target selection, instrument usage, and the spacecraft trajectories.[5][22] A NASA official who was present at the first Voyager meeting, observed that "Stone knew more about every one of their instruments than the P.I.s themselves knew."[22]
Stone also became a spokesman for Voyager, and became well known to the public in the 1980s, after he held dozens of press conferences announcing Voyagers' discoveries.[c][23] According to the Voyager project managerNorman Haynes, Stone "revolutionized the world of project science".[8][11]
Stone said that planetary encounters and the discovery ofvolcanism on Io were the most memorable events of the Voyager mission for him. He recounted the team's regular work process:[24][25]
There was a regular routine: In the afternoon we had a science meeting where individuals would say, "This is what we've seen" or "This is what we think" or "This is what we don't understand." Members from all 11 science teams participated, packing the conference room. These daily science meetings were a form of real time peer review that was also a way to choose which observations to report at the press conference the following morning. After the meeting, I would work with the investigators in outlining graphical illustrations that could be prepared overnight for use at the press conference at 10 a.m. In parallel, the imaging team would choose the images and prepare the captions for those that would be printed overnight for distribution to the reporters gathered at JPL. That afternoon, we would do it all over again with another day of observations and analyses.
Stephen P. Synnott recounted how Stone let him name a moon of Jupiter that he discovered on Voyager photos in 1980, saying "it looks like you've found yourself a moon" after checking the calculations. Synnott choseThebe from a list of names suggested by theIAU.[26]
Becoming Voyager project scientist was the best decision I made in my life.[4]
[the Project Scientist served] an impedance matching function between the engineering requirements and constraints and the science requirements and constraints to try to find a way to achieve the optimum match between these two different sets of requirements and desirements.[27]
Stone was the main advocate of the Voyagers. After the last planetary encounter he was able to receive funding for an extended mission, the Voyager Interstellar Mission. The Voyagers became the only spacecraft that left Solar System intointerstellar space.[28][22]
Jamie Rankin became Stone's last PhD student. Her thesis was on the Voyagers' interstellar space data; she graduated in 2018 and became the Voyagers' deputy project scientist in 2022. Before Rankin, Stone refused to advise graduate students for about 25 years.[2][29]
The Voyager mission visited all four giant planets and is the only spacecraft that visited Uranus and Neptune. It is NASA's longest-running spacecraft mission. In 2022, Stone retired after holding the role of the Voyager project scientist for 50 years.[30]
Though Stone is better known as the Voyager's project scientist, he served as aprincipal investigator for multiple other missions.[d] He was the PI of the Cosmic Ray Experiment onOrbiting Geophysical Observatory-6 (OGO-6, 1969), the PI of the Electrons and Hydrogen and Helium Isotopes experiments onInterplanetary Monitoring Platform 7 (IMP-7, 1972)[10] andIMP-8 (1973),[31] was involved into the cancelledASTROMAG (1980s),[8] was the PI of two instruments of the cancelledInternational Solar Polar Mission (1981),[32] the PI of a heavy-ion counter on theGalileo mission to Jupiter (1989),[33] the PI ofSAMPEX (1992),[32] the PI for theAdvanced Composition Explorer (1997),[34][8] and co-investigator ofSTEREO mission's High Energy Telescope (HET) and Low Energy Telescope (LET) (both part of the In-situ Measurements of Particles and CME Transients (IMPACT) instrument package) (2006).[35][36] Stone also "oversaw the redesign of the cooling system" on theSpitzer Space Telescope (2003),[13] and was an investigator on theIntegrated Science Investigation of the Sun instrument on theParker Solar Probe (2018).[37]
In 1991, Ed Stone–a well-known, enthusiastic and respectable scientist–was made the JPL director.[38]: 207 His directorship was during the difficult period of the 90s: with theCold War and theSpace Race between the US and the USSR finished, NASA saw dwindling budgets and introduced the so-called"faster, better, cheaper" approach, that encouraged smaller, cheaper missions built with the help of third-party contractors, efficiently "commercializing" the research lab and forcing it to work with industry.[38]: 208, 254 Cost-cutting had to be done by Stone, who tried to adapt a new management culture at JPL, while at the same time trying not to hurt science.[39] The plans were to downsize the lab and fire around 30% of JPL personnel by the end of the decade; Stone and Caltech leadership even feared that JPL could be closed.[38]: 208–209
The "faster, better, cheaper" (FBC) approach was described as:[40]
Faster applies to project development time, which for convenience can be defined as the period from project approval to launch. Rapid development cycles help control costs and enable the incorporation of the latest advances in technology, because the design freeze date is closer to the launch date. Better applies to the capability of the flight system as a scientific instrument, improvement here is based on the use of advanced technologies, and on better-focused science based on the knowledge gained from earlier exploration missions. Finally, cheaper denotes both lower cost per mission and, through clever design and use of technology, more effective use of available funds.
JPL had little experience in small missions at the time: its "flagship" missions, likeVoyager,Cassini, andGalileo, employed hundreds of people for decades. Cassini, for example, "directly supported maybe 500 work-years, about 10 percent of total lab staff [and] provided close to 20 percent of the lab budget".[38]: 223 In order to comply with budget restrictions and save the mission,Cassini was downsized; to save $250 million, the scan platform had to be removed from the plans.[38]: 260–261 Stone himself saw the "faster-better-cheaper" as a cultural change of the lab's engineering practices.[38]: 223
Stone also became a proponent of a management culture change at JPL, and installedRichard Laeser (former Voyager project manager) to applytotal quality management (TQM) at all levels. Reorganization was required to meet NASA needs, and TQM "emphasized customer service", even though few people at JPL saw NASA as their customer.[38]: 230–232 Many employees were against the new management practices.[38]: 223, 240 [e]
The most successful, "model" example of an FBC mission was theMars Pathfinder lander and the first Mars rover, theSojourner. The mission cost around 200 million dollars and was widely reported in the press, appearing on the covers ofTime andNewsweek.[38]: 267–270 Other missions were less fortunate: in 1998–1999, six missions were launched; four of them failed, including two Mars orbiters.[38]: 276 Both JPL (Stone) and the NASA administration (Daniel Goldin) acknowledged that they pushed too far with the FBC; no project manager of the failed missions was fired.[5][38]: 283
According to Peter J. Westwick, as the director of JPL, Stone was a "cautious revolutionary". He retired in 2001; his successor,Charles Elachi, "felt no need to change JPL's culture".[38]: 287
Stone retired from Voyager in 2022, after holding the role for 50 years, but remained professor emeritus at Caltech. He died in Pasadena, California, on June 9, 2024, at the age of 88.[11][13]
Stone was a shy man, and worked 100-hour weeks at times.Alan C. Cummings, theCosmic Ray Subsystem co-investigator, who worked with Stone for fifty years, described him as "very calm ... the smartest guy I ever met. He was a multiplexer supreme."[41] Stone was profiled in 1990 forThe New York Times by Michael Norman:[8]
A space scientist has to be a visionary, a poet in a white lab coat who can give voice to our collective craving for adventure, our fascination with a universe we have not been able to touch.
At first sight, Ed Stone is not such a man. As he hurries through the luminous California morning, one hardly notices him, 5 feet 10 inches, 130 pounds, a wisp in gray—gray suit, gray shirt, gray felt shoes[f] – lugging an ancient leather briefcase. He keeps to the shadows and side paths, terra incognita, a physicist so swept up in his daily occasions, so occupied by science, his life appears to turn on little else.
And yet, for the public, Ed Stone has been a kind ofCicero on space. As chief scientist on Project Voyager, he has participated in some 60 public briefings and news conferences over the 13 years of the project.
Stone met Alice Wickliffe on ablind date at a comedy club and married her in 1962. She died in December 2023. They had two daughters, Susan and Janet. Stone was described as a "shy man, sometimes diffident, often detached"; his younger daughter compared him toStar Trek'sMr. Spock. He had no close friends but "shared a long professional kinship with several scientists". He was a registered Democrat but not very interested in politics. Norman wrote that "He has no interest in sports, no hobbies ... His main recreation is to read a daily newspaper. His favorite food is raisin pie. He is not a man of faith."[8]
The Voyager mission became the longest NASA mission; Stone described it in 2012:[3]
When I started on Voyager my two daughters were young. By the time they were in college we had passed Saturn and were on our way to Uranus. They got married and the Voyagers just kept going, and we had grandchildren and Voyager just kept going and our grandchildren are now aware of what's happening to the Voyagers just like our children were.
He appeared inThe Farthest, a 2017 documentary on the Voyager program.[42]
In 2002, JPL established the Edward Stone Award for Outstanding Research Publication, which is awarded annually to JPL employees in both science and engineering.[43]
In 2012, a middle school was named in Stone's honor in Burlington, his hometown.[44]
In 2013, Stone was awarded theNASA Distinguished Public Service Medal, the highest NASA award for non-governmental employees. NASA arranged the award ceremony to be performed duringThe Colbert Report night show, with the award presented byStephen Colbert dressed in aretrofuturistic spacesuit. Stone was unaware of the award when he came to the show. It was given "for a lifetime of extraordinary scientific achievement and outstanding leadership of space science missions, and for his exemplary sharing of the exciting results with the public."[45]
In 2019, Stone won theShaw Prize in Astronomy, "for his leadership in the Voyager project".[46] The award included $1.2 million; Stone endowed a summer student program with this money "in return for the wonderful mission [Flandro] discovered".[47]
In 2023, theW. M. Keck Foundation endowed the Edward C. Stone Professorship at Caltech. Christopher Martin, director of Caltech Optical Observatories, became the first Stone Professor.[15]
In 2024, the Edward Stone Voyager Exploration Trail was unveiled at the JPL campus to commemorate Stone and his "penchant for walking". The trail starts at JPL Mall and consists of two paths, made similar to Voyager 1 and 2 trajectories. The trail features 24 memorial plaques, designed to "evoke theGolden Record" commemorating the mission's and Ed Stone's personal milestones.[48][49]
This article incorporates text from this source, which is in thepublic domain.
| Academic offices | ||
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| Preceded by | 7thDirector of the Jet Propulsion Laboratory 1991–2001 | Succeeded by |
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| National | |
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